I am a former ROHN engineer and have designed guyed towers up to 1000’. The guyed tower is the most complicated structure I know of. To analyze a guyed tower, you first have to analyze it for the gravity loads and the guy loads. These gravity loads shorten the tower and slack the guys. Then you have to take those results and apply the wind and/or ice loads. This analysis is done with custom software. We once had GT Strudl come and interview us on how we modeled the guy wires. Guy wires creep as loads are applied and the guys do not return to their original length when unloaded.
You’ve made me consider aspects I never even thought of before. For me, I was more of a user of the tower, rather than understanding the intricacies of the tower structure. This is why we hire experts in this field who understand these aspects. Thank you for the insight!
@@TheBroadcastEngineer There are many very interesting attributes about towers you might never notice. Like on an AM tower ROHN would design a 3’ cap. This is higher than the normal 6” cap on non AM towers. Why? Tall grass sometimes grows next to the tower and the morning dew from the grass can short the tower to ground and also create a fire hazard. Climbing, Towers are supposed to have either a climbing ladder or step bolts. Fall arrest devices (safety climb) are added to conform to OSHA and require a safety harness that fits the tower safety climb. Only the safety climb manufacturer’s harness will work with the manufacturer’s safety climb. A safety climb is a small cable positioned over the ladder that the climber clips into and prevent falls. A high liability item. Large 2000’ towers have elevators. 2000’ is the hight limit for towers in the USA because of the FAA rules.
I climb towers all across America for a living and on a windy day (20-40mph) climbing guy towers are absolutely terrifying and the fact that towers are just bones there's no shielding from the wind, on occasion I've actually had to stop climbing and just hold on for dear life!!
Back in the 90s, I used to work on towers, SST, Guyed, and mono poles. ROHN towers were my favorite towers to work on. And yes, there is more to a guyed tower than people realize.
Trucker here based in Birmingham AL. Many years ago I used to haul many Rohn shelters built in Bessemer AL. Most were cell site and fiber optic regen sites set from Cali to Texas to New England. Sometimes I had to get the gen sets for 3-4 locations. That was not fun
All extremely interesting and informative. During the 1980s I worked at a TV station, and I knew the engineers. Some of what you covered, I already knew from being around them. One night during storm season, our local power grid took a hit and knocked out the power for the lights on the tower. The chief engineer was there because it was a pretty bad storm, and he notified the FAA immediately. Tower height was (still is) 1,602 ft. Things were resolved with no incidents after it was over. They took me up the tower in the small elevator one time, I wish I'd had my camera with me. Elevator topped out at 1,492 ft. Later, they showed me a complete diagram of the tower with everything mounted on it; station equipment, lights, color banding lengths, other companies' lights...literally everything. I had no idea. I was impressed. Towers never look as big in size from a distance as they really are. Triangle shaped with a 8 or 10 ft spread between the legs (it's been so many years) with a small two-man 'box' for the elevator in the middle. Now, as a licensed amateur radio operator (yes, I'm a ham), our towers are not nearly as massive or complex as broadcast towers, but there are similarities on a smaller scale. But even when we need to do tower work, the most important factor is SAFETY. Not only for the climber, but also for the ground crew. I will share this video to our local ham clubs' Facebook pages.
CQ CQ. My extra class expired many years ago. 45 years ago. I still remember Morse Code, enough so that I do it to passing road signs. When valid I only worked CW. Call sign was .- - -... ....- .- -. - -. - -. -.
Great timing. Sunday I took a drive to the transmitter site of an AM station I used to run. Phased array, AM 5KW day 1KW night. I was reminising about the time I spent maintaining it and the associated equipment. Before modern air navigation systems were introduced we were the station used to navigate cross country and to the local airport. Fun memories.
@trbowlin, glad you mentioned broadcst AM towers as radio navigation aids. Although not commonly used by pilots today because VHF and satellite nav are the current standard, many (usually older) aircraft are still equipped with ADF or Automatic Direction Finding equipment that is basically a type of AM radio receiver with directional sensing and a panel-mounted display with a dial type compass indicator and a rotating pointer needle that indicates relative bearing to station, analogous to signal strength. In the early days of aviation a pilot or navigator sensed direction to an AM broadcast station manually by rotating a steerable loop antenna below the aircraft, looking for peak signal at a selected frequency. This was called 'DF.' Tune, identify station by call letters or other info ("...and the weather in Ft. Wayne is...) then simply rotate the antenna and listen for highest volume over the speaker or earphones, or observed a signal-strength meter or small oscilloscope tube for indication of peak reception. To this day a small part of the Khz band of the frequency spectrum is still dedicated to omnidirectional broadcast beacons and directional marker beacons used by the FAA for air navigation and as position markers on certain terminal-area flight procedures. Their exact locations and broadcast frequencies are noted on aeronautical charts. Normally they are modulated to emit a three-letter Morse identifier which is repeated at regular time intervals and heard onboard the aircraft to verify station ID, but some can also carry voice. Commercial AM broadcast towers are a useful form of navigation aid and in most ADF-equipped aircraft you can also listen for entertainment and general information. FAA radiobeacons are adjacent to commercial AM on the spectrum and have lower frequencies.
My buddy Patrick Griffith was an expert at all things radio. He wrote a book on all of this and AM radio towers. He knew every radio tower West of the Misssissippi. He was based in Denver and worked as a Firefighters/EMT. Miss that guy alot. RIP
I had been hoping to eventually get in contact with Patrick. I was the operator of a 'not-at-all' Part 15 AM in Central NM and he eventually stumbled upon it while passing through. Based on your comment, I am too late. Maybe I can at least find a copy of his book.
When I was growing up in the Detroit area in the 1960s, there was an FM station in Oak Park, WLDM (Lincoln Broadcasting), that very much had a homebrew feel to it. For example, when they started broadcasting in stereo, they bolted a couple of stereo faders to their mono broadcast console for the turntables. Advertisements were played on mono Ampex reel-to-reel tape decks, and the microphones were all mono. They had a freestanding tower; it looked kind of like the Eiffel Tower (and had no safety fence around it). To hoist stuff up the tower, they had a hook hanging from a big ball (probably a weight to make sure the hook came down easily when empty). The cable went up to a pulley at the top of the tower, down to a pulley anchored to the ground, and over to an old pickup truck that had had one of its rear wheels replaced with a large spool for the cable. I never saw the setup in use; I am really hoping that the did not hoist people that way. Eventually they got bought out by a large radio chain, who tore out all the homebrew stuff and replaced it with "best practices" engineering.
A cool non-radio tower fact: when they’re putting aircraft lights on a wind farm, all the lights blink on and off at the same time, so that it registers to pilots as one big obstacle. It’s a remarkable sight at night, no matter whether you’re on the ground or in the air.
Interesting. I wondered about grounding towers, as I've observed sparks upon disconnecting coaxial connector when it's windy, obviously static. I would imagine that one of those sticks would aquire quite a charge, setting RF aside! I would like to see a video on directional arrays, suppression to protect orher stations, and the like. I realize that might not be an easy subject to cover in one video... All the Best! 73 DE W8LV BILL
Ungrounded towers can develop a pretty good static charge. Even Series fed towers - ever see/hear St. Elmo's Fire? He also refers to being zapped by a tower receiving RF energy from nearby RF sources, like other towers in a multi tower array. Before working on a tower in a directional array, you need to detune/ground the one on which you are working. This includes feedlines and tuning components. Never leave home without your Jesus stick and ground strap.
Seems to me that a drain resistor would take care of static charge. Some high enough resistance that the transmitter wouldn't care, but low enough to effectively bleed off charge.
‘Used to climb towers for a living. Mostly AT&T cellular work but I’ve relamped FM & AM towers as well. Sometimes I do miss it. Most of the time I don’t!
Modern tower lighting is monitored remotely and the monitoring company could be in another state but when either beacons or obstruction lights fail they are notified through a ring down line and the FAA is also notified and they either have a tower company on standby or a list of companies that get dispatched for service ASAP. I worked for Leblanc and Royal and at the time they were the world's largest tower erector and manufacturer and they offered a service contract guaranteeing 400 feet of tower in 24 hours for emergency replacement.. they still make transmitters that are some of the best compared with Harris or dielectric.
Was only in radio about 8 years but in that time, at a small (with an even less than lowercase "s") market station, part of my job was hanging with the engineer. Without going into detail, there were a few times your advice @16:10 wasn't in the equation. Due to an abundance of caution, I'm here to mention that but it gave me an appreciation for the pros in the 30+ years since.
There aren’t any stations in the Los Angeles market that will risk their engineers by putting so much pressure that they feel they have to climb the tower “or else.” In a small market, it’s just not worth the risk. Especially if the #1 or #2 markets aren’t exerting that kind of pressure.
Kickass. This was a great video and many great insights from industry professionals in the comments. I'm almost 5 decades on and I still have a constant thirst for learning.
Thank you for posting. I am retired from radio after a 48 year career. This is good info for the public in general who otherwise would not be aware of the dangers associated with these sites. Standing under guy wires can even be a hazard where melting ice or in some cases hardware can fall off causing serious injury or death.
Yes, I forgot to mention the ice off the guy lines. I’m finding a lot of people are coming from the IT world being thrust into the broadcast engineer world. There isn’t usually an ice danger fixing someone’s printer.
So glad you said guy lines instead of guide lines like so many people do. I've been a subcriber for a long time. I like to learn things from people who know what there're talking about.
Got into a pissing match with a keyboard warrior once. He will go to his grave convinced they are guide wires. You cannot each he who will not learn, alas.
Not all AM transmitter towers are the transmitting antenne themselves. The shortwave broadcast transmitters use towers with wire antennas hung up between them. Giving them even some kind of directional working, to aim the signal to a certain area of the world. However these AM broadcast shortwave stations are declining in numbers. The shortwave (and medium wave) transmitter site here in the Netherlands at Zeewolde, 43 km east of Amsterdam was used by several broadcast stations, but is now used by the military.
Because there aren’t many shortwave stations out there. Hasn’t been a new shortwave station in the US for many many many years. Most that are left are falling apart and once something dies they’re gone for good.
Maybe some tower trivia few know. The Foley Artists, the people that search foir sounds for movies, were looking for sounds for Star Wars. They were at a tower, (FM, I hope) and struck the guy wire. They loved the sound and it became the sound of clashing light sabers.
I noticed Magnum Towers in Sacto is still in business. I built a number of TV stations with them in the 80's. Proper tall tower site operation takes a lot of management and money. Mt Sutro, was my favorite.
Erecting a tower without a crane is done using a ginpole. The gin is short for engine as in physics it is a type of engine. Basically it is a small crane boom that is suspended from the side of your stub,( tower base ) and using a winch to raise sections into place. You bring up a section, swing it in to place, bolt it down and jump the pole for your next section. Stacking self support towers is more complex in that you bring up the legs and then to bring up the faces requires horizontal movement of the ginpole. to explain it sounds complicated and you need to understand some rigging principles but watching it done makes it look simple. Fun fact. Self support towers are built with only the legs tightened at first and then from the bottom up the faces are tightened one at a time which makes the tower plumb or straight. Otherwise it would look like a banana made of sticks.
I used to live about a mile away from these two towers. I had the opportunity to talk with the crew when the north tower was being constructed. They were camping out overnights at the tower and I learned quite a bit about their process. I also learned what a BIG gin pole looks like, compared the little u-bolt and pipe thingy I helped my buddy with on his amateur radio tower. I am very grateful that these high intensity strobes are reduced at nighttime. I remember when these ones underwent a burn-in period and operated at full intensity continuously for around a week. The flashes made it difficult for me to get to sleep at times. The intensity required for daytime visibility is pretty amazing.
The FAA rules on tower paint don't specify color other than red. Most are painted aviation orange. Which looks red. If the tower is on a flight path and over 200 feet it must be painted and lit. The rule is 7 bands with red at bottom and top. The beacons,( flashing lights) must be red at night and white during the day. The non flashing lights in between the beacons are side marker lights. Beacons must be 200 feet apart.
I was a geology student at Caltech and the 1992 Landers earthquake happened during my summer research fellowship. The surface rupture went right between the legs of one of those giant electric power towers. Peak horizontal offset was 18 feet and somehow miraculously THE TOWER DIDN"T FALL!!!
It depends on where the antenna is located. If it’s on a tower more than a regular ladder or accessible from a bucket truck then I’d hire professionals. Just be sure the station is off before you get close or touch the antenna.
I work with industrial machinery. You take lock out tag out to next level. I used electric fence for years. I'd scan the AM band and listen for shorts to earth. I've been that path for electric potential, not fun. I also use our radio tower local, as a land mark looking for the lights.
Fascinating. I grew up in the 50s and 60s and got my ham license then too. Where I lived in Central NY I could see newly constructed TV towers from miles away with the blinking red lights and often wondered how in the hell they built that thing because it wa the tallest structure around. then I wondered about the feed lines to the tower being that TV frequencies are shorter than AM and FM , where in the tower is the feed point? How is the tower fed especially with all that cabling that would reduce power by reactances? It must take special feed lines doesn't it? Much to learn here...Thanks
Worked ground level at many antenna sites. Been there during lightning. Is it safe or more dangerous to be in the vicinity of a well grounded tower. Versus the open field
That’s a good question. I would think a little safer because the lightning has a path to ground, but I’d still try to stay inside a building or shelter than at the base of the tower.
When I was a student at Cal Poly San Luis Obispo back in the early 1980’s, I was a DJ on the school radio station my senior year. There was a small hill on the east side of the campus called Radio Hill. There were two radio antennas, one AM antenna for a local public station, and an FM antenna for the school radio station. The AM antenna was rather large and very prominent. The school’s antenna which consisted of a wood pole with a stick antenna attached to the upper part of pole, was barely noticeable to anyone viewing it. The station at that time was only 2 kW. Most people assumed the large AM antenna was for the school station. The school antenna has since been relocated to the top of Cuesta Grade, at the north side of town. I’m not sure if the power was increased, but the service area extends like 30 miles from antenna out. The signal from transmitter to antenna back in the 1980’s was carried by two telephone lines for the stereo broadcast. As part of our DJ training, we had to know FCC rules and regulations in running a radio station as well as handling EBS tests and events. We were a secondary radio station in the case of an emergency for our service area. Each trainee who became a DJ also had to apply and receive an FCC license to operate a radio station.
We used to climb those in my youth. The ATT long lines had tons of microwave antennas in horns or "drums" That if you stood of in front too long you would get a head ache any candy in your pocket melted and the fun part of having you nose and ears bleed and one time my friends eyes bleed, but not really any pain. .
I recognize the two towers at the beginning of the video. They are 20ish miles north northwest of Denver International Airport. Towers can actually be difficult to see from the air, they can blend in with the ground under certain lighting conditions.
You have to be carful with the county road to access those towers as it can get quite muddy as I discovered. I stopped by there once (from road) when in town, and was heading up to Berthoud to visit my brother and had always seen these towers from I-25 nearby. One of them is KDEN-TV and the other is a KKSE-FM "Altitude Sports" Coordinates of KDEN tower 40°05'57.0"N 104°54'03.2"W at 1243' above ground. Nearly all Denver metro stations are on Lookout Mountain near Golden.
As an Extra Class HAM this stuff is cool…great job…if it paid more I definitely would have gone into broadcast engineering…I went to school back in the early 90s and worked on my doctorate in the mid 90s…but have and still am volunteering for our local public TV station …I use personally a large telescoping antenna (12 meters) because I’m mobile most of the time…
How TH-cam didn’t recommend this channel is beyond me. When a local cell tower was being built close to my house nearly 20 years ago, I’d go over at least once a week (I’m 39). I got to know some of the tower crew, and shed engineers. Sadly I never kept in touch much. But I still will stop at the tower if folks are working on it, and ones near by it too.
@@TheBroadcastEngineer They seemed to enjoy sharing their knowledge and experience with someone also interested in Radio Engineering. Nice to know they’re not the only ones. :)
We get pretty lonely on the road. Most of use travel a couple weeks straight at a time fixing towers all across the country!! Just don't catch me on the last day or two, way too exhausted to entertain or talk 😔 normally we climb at least once a day, sometimes 2 or 3!
The safest place to be during a thunderstorm,( if you have to be there at all) is on the tower away from the bottom and top. The tower has a faraday effect letting the lightning go around you to ground. More than once I've had to move to the middle of a tower, belt off, cover my ears and wait it out. Iv been essentially struck by lightning dozens of times because of this. At the top you become the lightning rod and at the bottom it can arc to a good conductor which being mostly water you are. It's actually safer to be on the tower during a thunderstorm than it is in the equipment shelter even though the transmission lines have lightning arresters because occasionally there are strikes that exceed the limits of an arrester enter the equipment room. But no matter the power of the strike the tower just takes it around you safely to the ground network. When establishing critical path for a tower site lightning is an important factor in determining whether grounding should be before or after erection begins..
@@TheBroadcastEngineer you covered it well it was very interesting, can you do a video sometime on what the power of the signal does i.e when they say the signal is 160kw or 5 kw, and what the advantage of height does, not only by being on a mountain top but the way national tv and radio tends to be at the top of a mast and the local station ( at least here in Ireland tends to have the radome or antenna nearer the bottom, that would be interesting ( i meant megawatts not kilowatts) 🫣
Thanks Marcus, and as well that often towers also carry lots of other services on them, so climbing them more than a foot above the ground also requires that the other co users also are notified, and that they also safe their equipment. especially true for climbers, but even you could be just on the base connecting a new cable to your side, and the RF is not the greatest thing to have.
In the 90s a small tornado hit cedar rapids Iowa and felled a 400 foot guy tower across the parking lot and back of the building where they made universal gym equipment. 15 cars were flattened and 2 people were killed. We had to go and move the mangled tower to a nearby field and put up a new one. Start to finish 6 days.
I worked somewhat near a series of tall transmission towers well fenced in without much built up around them. I had a coworker who grew up closer to them, and who said sadly that she’d watched one tower fall during the build. She reported seeing workers fall, apparently not tethered, not that it would matter at that moment… We also had railroad tracks by the worksite, and a switching yard was almost in the backyard of her family home. One day early in my employment at the job I commented upon the series of black painted rail tanks rolling by. My coworker asked if I knew what was in the tanks. I hadn’t read the white lettering, and stated that I didn’t know. “Anhydrous ammonia. That stuff will burn out your lungs if the tank leaks!” YIKES!! Only decades(!) later, after thousands of those A.A. tank cars had creaked past the facility the employer instituted safety drills in the event of a rail accident; where to go, what to shut and shut off, who to call, etc. One thing noted about the antenna guy-lines are the weights riding upon the lower limit of the cable before they terminate at the anchors! We have snow and ice here in winter. Obviously there is much wind at heights. Temperature contracts and expands material. I have long wondered how much “give & take” any particular guy line is subject to!! Great episode!
@williesnyder2899, the guy wires are almost completely inelastic. They 'give' a bit under gravity and dynamic loads such as wind, ice accumulaton or seismic activity but, essentially, do not 'take' to return to original length or tension. From time to time they need to be retensioned properly to maintain the straightness, vertical alignment and overall structural integrity of the antenna system. Not unlike tuning a stringed musical instrument.
In college I remember a large FM broadcast tower that fell across the street from my dorm. One moment it was standing up, then, it was gone! Someone had cut a guy wire and caused its collapse.
Very interesting information for a lay man. I live over the big pond in the UK. Near my locality is a Tv/radio mast called Winter Hill just outside of a small town called Egerton. There is also a aircraft crash site a few hundred yards away. The aircraft did not strike the mast but I believe it was bad weather that caused the incident. You learn something every day. Thanks for the great video 👍
I lived in the UK for about 5 years, first in Manchester, and then up near Blackburn. Winter Hill was an impressive transmitter tower to see, it was huge.
When I was in electronics school back in the 80's I learned that TV broadcast was done through a port-hole from a tube. I also learned that CB radios don't have much power on their antenna when under broadcast but no voice. Start speaking and the wave peaks around 400V. That'll brighten your day!
I went to DeVry in the late 80s. It was a great school. I went there because of my interest in all things radio since I was a kid. AM, FM, CB, etc. transmitters, receivers, amplifiers. Still have a fondness for it all. Wish I could put my interest to good use.
Worked at an electric company and it was frustrating that the orange red marking paint would fade and need repainting every 10 years. Bad enough to do it once but worse over and over. There was a color chart to see if it had faded.
I didn't realize that AM radio towers were that dangerous! Good to know! I do have a question, though. The RF energy being transmitted at a radio station, can it have negative affects on the human body when one is very close to them while they are operational? For both AM and FM. I know microwave transmitters have the capacity to cook a body like our home microwaves do for our food when one is in direct line with the antenna, but I am curious if that is possible at AM or FM frequencies.
It’s all about wavelength and resonant frequencies with body parts. At AM frequencies not really an issue. FM frequencies will cause heating effects on some smaller body parts.
This is a hotly debated issue. It's called the effects of non-ionizing radiation on human tissue. Non-ionizing radiation is basically radio waves versus ionizing radiation like X-Rays, and radiation emitted by radioactive material. There is some evidence that children living under high tension power lines have a greater likelihood of developing leukemia than those that don't. Yet the people that work on those power lines seem not to be affected. Microwaves are kind of on the dividing line between ionizing and non-ionizing radiation. Some people think holding your cell-phone close to your body, especially your head may make you at higher risk for certain forms of cancer. Some people are really concerned about 5G cellular, since those towers have to be much closer to the user than the older technology. Now, having said this for every study that says there are these negative effects, there is another that says no, it's perfectly safe. Marcus is right, do not ever touch an AM broadcast tower, ever. I've drawn electrical arcs off the guy wires at an FM tower just running a screw driver over it. It could have been from static electricity and the place was pretty hot with RF. There were two FM stations on tower, and the NOAA Weather Radio Station, but it's only 250 watts. I've been messing with RF since I was a kid, I'm a grandfather now. I do maintenance on some Ham repeaters. These are located in areas where there are broadcast transmitters, cell phone systems, and other transmitters. I've been very close to a TV transmit antenna, and had my face inches from our own 120 W VHF transmit antenna. I developed cataracts when I was only 40. Did this behavior have something to do with that? I don't know. My doctors think they see some changes in my optic nerves, however my distance vision is still very good. So, they keep poking and prodding at me, but still no definite answers. I do know this for certain, the FCC and the EPA are now making us answer questions about RF safety on the Ham tests, and we are supposed to do an RF safety evaluation on our stations. Even though the highest power level we can run is 1500 watts PEP. Most of us on our VHF and UHF stations seldom exceed 50 watts if that much. Pretty tame compared to broadcast transmitters. We once asked the engineer at a 50 KW AM station, what happens if you touch the tower while standing on the ground. His answer was, "you will disappear in a pink puff of smoke." Something like that happened to a would be copper thief at another AM transmitter site.
I wouldn't want to get a serious RF burn....I'm theorizing that there is enough current at a 50kW AM radio station tower. I wouldn't want to be these foolish Russian teens: th-cam.com/video/b9UO9tn4MpI/w-d-xo.htmlsi=x_M_tYHEk82dY6gD
I am a recent convert to DXing, mostly AM radio. I have begun to notice every tower I see on my truck route along coastal South Carolina. I never realized the complexity in a tower structure nor the challenges that must be overcome to maintain its integrity. How tall can a tower be erected without use of a sky crane helicopter?
1) Electrocution implies death. Shocked implies being in the path of the electrical current. 2) Not all AM towers are insulated, thereby "series fed". Grounded AM towers are "Shunt Fed". They are excited by a sloping line up to a certain point on the tower. They are relatively safe to touch, but as you say, you should not be there in the first place unless you are an authorized professional with an official reason to be there. 3) Towers are by regulation enclosed with a safety fence for a good reason. If you think you need to be inside the fence, most likely you don't Consult the tower owner or operator and explain your needs. That's a good way to get shocked, burned, have things fall on you or even encounter fast moving articles made of lead. -- 62 year Consulting Engineer, Broadcast engineer, tower climber. Retired, Denks Gott.
Question about what you said when using standard vehicle jump cables to ground the antenna…are you saying the balls you would hook one part of the cable to doesn’t hold electrical currents? And obviously do this when the transmitter is off. I had to rewatch that part a few times to understand it how to ground the tower. You said connect end of the cable to the tower itself then the ball. You had also talked about how a tower can also be a good receiving antenna and currents still be carried if that tower’s transmitter is off completely if I understood that correctly. How is it that when connecting a jumper cable to a bare metal part on the bottom of the tower still couldn’t carry electrical currents and one not get electrocuted?
If you look at the balls, one is connected to the tower and one is connected to ground. You basically want to jumper those together without moving them. You're just grounding the tower. Yes, you want to have the transmitter off, otherwise, you could risk damaging the system.
The specifics of how to short a tower are probably best not explained in a public forum like TH-cam for safety and liability reasons. People who have intentions on climbing without permission or training might think they know what they're doing and get it wrong. Most likely ending in a fatality.
Guyed towers are pretty common in the world, here in europe there are so many, in poland many over 300 meters tall and in france, germany, UK a few taller than 300 meters.
I have a quesion and a suggestion. How do AM stations change their daytime/nighttime patterns? I'm guessing that it's done with relays to specific radials. I also watch another TH-camr, Jeff Geerling, He does a computer oriented channel, his father is, or was, the engineer for KMOX in St Louis. He had an interesting video of some of the KMOX radio transmitter equipment. Perhaps you could include him in an episode.
Directional AM stations have at least two towers. The output from the transmitter goes into a "phasor" that controls the amount of signal that goes to each tower and the phase between each. If you did any vector analysis in trig class, you will recall that different signals will add and subtract with time. This translates to more signal radiating in some directions and less in others. When a pattern change is done, relays do change between the controls for the daytime and nighttime pattern. Sometimes, even a tower or two are energized or de-energized depending on the need. I used to work at a four tower directional station but we only had one pattern. This was in the 70s and stations had to keep a first class licensed operation at the transmitter. There wasn't much else to do, so I manually calculated the patterning using the information from the phase monitor. I used an add, subtract, multiply, and divide calculator and a slide rule for the trig functions. It was necessary to calculate two patterns using two towers then use those figures to calculate the finial pattern. Signal strength was calculated at 10 degree increments. Imagine my surprise when I plotted the pattern and it came out reversed. I missed a sign somewhere. It was a good exercise, but I didn't do it over.
@@michaeldaniels3639 thanks. Yes, I'm acquainted with a phased array antenna from my amateur radio hobby. I was unaware that AM stations use multiple phased towers. I was guessing that it was by using relays to activate / deactivate ground radials.
My first BASE jump was off of a tower-1250’agl. My first night BASE jump was also a tower jump-900’agl. I can’t drive past a tower without looking at it and accessing it’s “jumpability”.
Against my best advice, my friend touched an energized one of the two WIP am towers at their tx site in NJ. We had to call an emergency squad from Westville to keep him alive. Fortunately he learned his lesson. I keep telling people to just stay away from these places! Look but just don't touch!
Wow 8 hundred thousand feet tower. That's huge. Thanks for the great video tho. I don't know why but towers that are higher than a certain amount scare me. I can be mikes away and just looking at them they freak me out
Thanks for the video I always wanted to build a radio tower maybe you could tell me some tips to build a model one I'm making a small model one so I know what it looks like in the future
What scale model and what are you using as a media like toothpicks or model car sprue. Also what type of tower are you building, self support, guy tower, monopole, horizontal billboard?
I don't know where you got 800,000 feet tower but no. The maximum height in the u.s. is 2000 feet of tower and there can be up to 200 feet of antenna on top allowing a 2,200 foot maximum to the top beacon. In Russia there were a couple of 3000 foot towers but one fell leaving one.
@@TheBroadcastEngineer Its getting bigger again WRMI Legends on 5050 & 9455 kHz, WWV & WWVH 2.5, 5, 10, 15, 20 & 25 MHz, WWCR 3215 & 4840 kHz, WTWW, 5085 kHz & WBCQ 15420, 9330, 7490, 5110 kHz to name some as well as many overseas.
Ive been building towers for 30 years and the most terrifying task of them all is changing out guy lines. I know of at least 25 men killed on tower sites from the tower collapsing but not a whole lot of straight falling themselves. Im hoping to never be on a 1000 footer that collapses.
Laying on top of an old Western Electric KS-15676 horn antenna while looking at the summer night sky. Was always worth the horrifying 250' climb back down. 🛰️ ✨ 🌖 ✨ 🪐 🛸
The question of can radio frequency radiation commonly known as RF Cook a person. You betcha. I was putting a quarter wave dipole up for an FM station in Orange California and setting azimuth was a challenge because up there there is nothing to push against so I got between the antenna and the pole it was mounted on and immediately felt my body get hot from the inside. All RF is dangerous depending on proximity and duration and power level, regardless of frequency. If you were to get in the path of a 2 gigahertz studio tower link for TV you would be fried just the same as walking up and grabbing an am tower. Occasionally it happens that birds will fly in such a path and zap. They don't explode or go down in flames but they do literally cook on the inside and fall out of the sky. RF radiation excellerates the water molecules the faster they move the more heat is created which is why some things can be cooked in a microwave oven and some things shouldn't. Objects with no water molecules like foil repel radio waves that's why foil sparks and can ruin your oven. It reflects the power back into the transmitter kinda like if someone were to shoot at you with a laser and you put up a mirror and bounce it back at them.
Maybe consider facing an alternate Direction during your introduction because there's a massive shadow distracting from your face. Maybe gets a reflector to light the other side of your face. Your eyes are shrouded in darkness
Who can a civilian call to report a tower light out? One of the local radio stations (FM) has the top light out. Middle is still flashing. I used antenna search to find an email address. I sent an email telling them. It's been over a month. Light is still out.
@@TheBroadcastEngineer I bet they know the light is out and just don’t want to hire a climber just to change a few bulbs. Most white lights come with multiple bulbs that will switch when one burns out. Flashing beacons are a special type of light, expensive. Red light are out of style. Some people have a nervous reaction to red light, strange but true.
Often times we do LED upgrade installs, normally the guys will toss the beacons/side markers off the tower to save time and energy. Some of the older incandescent stuff is pretty cool, I collect a lot of the stuff we decommission and re engineer with LEDs for home display/entertainment purposes!
The FAA will not take a notification of a non lighted tower from anyone other than the tower's owner. Check your maps for towers and don't trust that they are lighted at night.
I am a former ROHN engineer and have designed guyed towers up to 1000’. The guyed tower is the most complicated structure I know of. To analyze a guyed tower, you first have to analyze it for the gravity loads and the guy loads. These gravity loads shorten the tower and slack the guys. Then you have to take those results and apply the wind and/or ice loads. This analysis is done with custom software. We once had GT Strudl come and interview us on how we modeled the guy wires. Guy wires creep as loads are applied and the guys do not return to their original length when unloaded.
You’ve made me consider aspects I never even thought of before. For me, I was more of a user of the tower, rather than understanding the intricacies of the tower structure. This is why we hire experts in this field who understand these aspects. Thank you for the insight!
@@TheBroadcastEngineer There are many very interesting attributes about towers you might never notice. Like on an AM tower ROHN would design a 3’ cap. This is higher than the normal 6” cap on non AM towers. Why? Tall grass sometimes grows next to the tower and the morning dew from the grass can short the tower to ground and also create a fire hazard.
Climbing, Towers are supposed to have either a climbing ladder or step bolts. Fall arrest devices (safety climb) are added to conform to OSHA and require a safety harness that fits the tower safety climb. Only the safety climb manufacturer’s harness will work with the manufacturer’s safety climb. A safety climb is a small cable positioned over the ladder that the climber clips into and prevent falls. A high liability item.
Large 2000’ towers have elevators. 2000’ is the hight limit for towers in the USA because of the FAA rules.
I climb towers all across America for a living and on a windy day (20-40mph) climbing guy towers are absolutely terrifying and the fact that towers are just bones there's no shielding from the wind, on occasion I've actually had to stop climbing and just hold on for dear life!!
Back in the 90s, I used to work on towers, SST, Guyed, and mono poles. ROHN towers were my favorite towers to work on. And yes, there is more to a guyed tower than people realize.
Trucker here based in Birmingham AL. Many years ago I used to haul many Rohn shelters built in Bessemer AL. Most were cell site and fiber optic regen sites set from Cali to Texas to New England. Sometimes I had to get the gen sets for 3-4 locations. That was not fun
All extremely interesting and informative. During the 1980s I worked at a TV station, and I knew the engineers. Some of what you covered, I already knew from being around them. One night during storm season, our local power grid took a hit and knocked out the power for the lights on the tower. The chief engineer was there because it was a pretty bad storm, and he notified the FAA immediately. Tower height was (still is) 1,602 ft. Things were resolved with no incidents after it was over. They took me up the tower in the small elevator one time, I wish I'd had my camera with me. Elevator topped out at 1,492 ft. Later, they showed me a complete diagram of the tower with everything mounted on it; station equipment, lights, color banding lengths, other companies' lights...literally everything. I had no idea. I was impressed. Towers never look as big in size from a distance as they really are. Triangle shaped with a 8 or 10 ft spread between the legs (it's been so many years) with a small two-man 'box' for the elevator in the middle.
Now, as a licensed amateur radio operator (yes, I'm a ham), our towers are not nearly as massive or complex as broadcast towers, but there are similarities on a smaller scale. But even when we need to do tower work, the most important factor is SAFETY. Not only for the climber, but also for the ground crew. I will share this video to our local ham clubs' Facebook pages.
CQ CQ. My extra class expired many years ago. 45 years ago. I still remember Morse Code, enough so that I do it to passing road signs. When valid I only worked CW. Call sign was .- - -... ....- .- -. - -. - -. -.
Great timing. Sunday I took a drive to the transmitter site of an AM station I used to run. Phased array, AM 5KW day 1KW night. I was reminising about the time I spent maintaining it and the associated equipment. Before modern air navigation systems were introduced we were the station used to navigate cross country and to the local airport. Fun memories.
That sounds like a very interesting story!
@trbowlin, glad you mentioned broadcst AM towers as radio navigation aids. Although not commonly used by pilots today because VHF and satellite nav are the current standard, many (usually older) aircraft are still equipped with ADF or Automatic Direction Finding equipment that is basically a type of AM radio receiver with directional sensing and a panel-mounted display with a dial type compass indicator and a rotating pointer needle that indicates relative bearing to station, analogous to signal strength. In the early days of aviation a pilot or navigator sensed direction to an AM broadcast station manually by rotating a steerable loop antenna below the aircraft, looking for peak signal at a selected frequency. This was called 'DF.' Tune, identify station by call letters or other info ("...and the weather in Ft. Wayne is...) then simply rotate the antenna and listen for highest volume over the speaker or earphones, or observed a signal-strength meter or small oscilloscope tube for indication of peak reception. To this day a small part of the Khz band of the frequency spectrum is still dedicated to omnidirectional broadcast beacons and directional marker beacons used by the FAA for air navigation and as position markers on certain terminal-area flight procedures. Their exact locations and broadcast frequencies are noted on aeronautical charts. Normally they are modulated to emit a three-letter Morse identifier which is repeated at regular time intervals and heard onboard the aircraft to verify station ID, but some can also carry voice. Commercial AM broadcast towers are a useful form of navigation aid and in most ADF-equipped aircraft you can also listen for entertainment and general information. FAA radiobeacons are adjacent to commercial AM on the spectrum and have lower frequencies.
My buddy Patrick Griffith was an expert at all things radio. He wrote a book on all of this and AM radio towers. He knew every radio tower West of the Misssissippi. He was based in Denver and worked as a Firefighters/EMT. Miss that guy alot. RIP
I had been hoping to eventually get in contact with Patrick. I was the operator of a 'not-at-all' Part 15 AM in Central NM and he eventually stumbled upon it while passing through. Based on your comment, I am too late. Maybe I can at least find a copy of his book.
Having dealt with NOTAMs, they are easy to do but easy to overlook and/or forget.
After that phone call from the FCC I never overlooked it again. Lots of post it notes and calendar reminders. 😁
Taking things off the NOTAMs is important. As a pilot, it is just another distraction to remember. Thanks for remembering to remove them.
When I was growing up in the Detroit area in the 1960s, there was an FM station in Oak Park, WLDM (Lincoln Broadcasting), that very much had a homebrew feel to it. For example, when they started broadcasting in stereo, they bolted a couple of stereo faders to their mono broadcast console for the turntables. Advertisements were played on mono Ampex reel-to-reel tape decks, and the microphones were all mono.
They had a freestanding tower; it looked kind of like the Eiffel Tower (and had no safety fence around it). To hoist stuff up the tower, they had a hook hanging from a big ball (probably a weight to make sure the hook came down easily when empty). The cable went up to a pulley at the top of the tower, down to a pulley anchored to the ground, and over to an old pickup truck that had had one of its rear wheels replaced with a large spool for the cable. I never saw the setup in use; I am really hoping that the did not hoist people that way. Eventually they got bought out by a large radio chain, who tore out all the homebrew stuff and replaced it with "best practices" engineering.
A cool non-radio tower fact: when they’re putting aircraft lights on a wind farm, all the lights blink on and off at the same time, so that it registers to pilots as one big obstacle. It’s a remarkable sight at night, no matter whether you’re on the ground or in the air.
Interesting. I wondered about grounding towers, as I've observed sparks upon disconnecting coaxial connector when it's windy, obviously static. I would imagine that one of those sticks would aquire quite a charge, setting RF aside! I would like to see a video on directional arrays, suppression to protect orher stations, and the like. I realize that might not be an easy subject to cover in one video... All the Best! 73 DE W8LV BILL
Ungrounded towers can develop a pretty good static charge. Even Series fed towers - ever see/hear St. Elmo's Fire?
He also refers to being zapped by a tower receiving RF energy from nearby RF sources, like other towers in a multi tower array. Before working on a tower in a directional array, you need to detune/ground the one on which you are working. This includes feedlines and tuning components. Never leave home without your Jesus stick and ground strap.
Seems to me that a drain resistor would take care of static charge. Some high enough resistance that the transmitter wouldn't care, but low enough to effectively bleed off charge.
‘Used to climb towers for a living. Mostly AT&T cellular work but I’ve relamped FM & AM towers as well. Sometimes I do miss it. Most of the time I don’t!
I’ve watched a lot of tower climbing videos. Fascinating but not something I could do.
How do you personally deal with the fear?
@@JeffMTXsome people don't have the fear
What a nice video, enjoyable and informative!
Modern tower lighting is monitored remotely and the monitoring company could be in another state but when either beacons or obstruction lights fail they are notified through a ring down line and the FAA is also notified and they either have a tower company on standby or a list of companies that get dispatched for service ASAP. I worked for Leblanc and Royal and at the time they were the world's largest tower erector and manufacturer and they offered a service contract guaranteeing 400 feet of tower in 24 hours for emergency replacement.. they still make transmitters that are some of the best compared with Harris or dielectric.
Was only in radio about 8 years but in that time, at a small (with an even less than lowercase "s") market station, part of my job was hanging with the engineer. Without going into detail, there were a few times your advice @16:10 wasn't in the equation. Due to an abundance of caution, I'm here to mention that but it gave me an appreciation for the pros in the 30+ years since.
There aren’t any stations in the Los Angeles market that will risk their engineers by putting so much pressure that they feel they have to climb the tower “or else.” In a small market, it’s just not worth the risk. Especially if the #1 or #2 markets aren’t exerting that kind of pressure.
@markdraper3469 I don’t understand…
@@TheBroadcastEngineer Sry.. oops on my part.
@@postal_the_clown No worries. I was just trying to understand. Oildale is in Kern County outside of Bakersfield.
Kickass. This was a great video and many great insights from industry professionals in the comments. I'm almost 5 decades on and I still have a constant thirst for learning.
Thank you for posting. I am retired from radio after a 48 year career. This is good info for the public in general who otherwise would not be aware of the dangers associated with these sites. Standing under guy wires can even be a hazard where melting ice or in some cases hardware can fall off causing serious injury or death.
Yes, I forgot to mention the ice off the guy lines. I’m finding a lot of people are coming from the IT world being thrust into the broadcast engineer world. There isn’t usually an ice danger fixing someone’s printer.
And in cold conditions, ice falling from towers can be fatal. Ice from our 2000 footer carried almost a mile away.
Thank you, I learned something today being an AM radio junkie for 60 years I did not know the entire tower is charged. That is amazing.
Awesome information. Definitely opened my eyes to tower engineering.
So glad you said guy lines instead of guide lines like so many people do. I've been a subcriber for a long time. I like to learn things from people who know what there're talking about.
Or like the automatic transcription put? 😂
Got into a pissing match with a keyboard warrior once. He will go to his grave convinced they are guide wires. You cannot each he who will not learn, alas.
It's spelled guyed wires.
@@dansteel9873 The tower is the guyed structure not the wires. I think you're confusing guyed and guide, two different words.
Not all AM transmitter towers are the transmitting antenne themselves. The shortwave broadcast transmitters use towers with wire antennas hung up between them. Giving them even some kind of directional working, to aim the signal to a certain area of the world. However these AM broadcast shortwave stations are declining in numbers. The shortwave (and medium wave) transmitter site here in the Netherlands at Zeewolde, 43 km east of Amsterdam was used by several broadcast stations, but is now used by the military.
Thank you. I was waiting for him to mention that and wondered why he hadn't.
Because there aren’t many shortwave stations out there. Hasn’t been a new shortwave station in the US for many many many years. Most that are left are falling apart and once something dies they’re gone for good.
@@TheBroadcastEngineer Not true did you forget about us Radio Amateurs ? :) I did get what you meant by that though..
@Ztbmrc1 Besides shortwave I believe WWVB in Colorado uses a dipole strung between towers.
@gatesmw50 on the bucket list…
Maybe some tower trivia few know. The Foley Artists, the people that search foir sounds for movies, were looking for sounds for Star Wars. They were at a tower, (FM, I hope) and struck the guy wire. They loved the sound and it became the sound of clashing light sabers.
As a retired Broadcast Engineer. I also owned a tower company and climbed towers. What you have provided is a good summary.
We have an awesome tower farm in Houston. Its also the place where a tower fell that was under construction...the senior road tower
I noticed Magnum Towers in Sacto is still in business. I built a number of TV stations with them in the 80's. Proper tall tower site operation takes a lot of management and money. Mt Sutro, was my favorite.
Erecting a tower without a crane is done using a ginpole. The gin is short for engine as in physics it is a type of engine. Basically it is a small crane boom that is suspended from the side of your stub,( tower base ) and using a winch to raise sections into place. You bring up a section, swing it in to place, bolt it down and jump the pole for your next section. Stacking self support towers is more complex in that you bring up the legs and then to bring up the faces requires horizontal movement of the ginpole. to explain it sounds complicated and you need to understand some rigging principles but watching it done makes it look simple. Fun fact. Self support towers are built with only the legs tightened at first and then from the bottom up the faces are tightened one at a time which makes the tower plumb or straight. Otherwise it would look like a banana made of sticks.
Excellent and very informative. Thank you.
This was great information about things in the world that you see everyday and I knew nothing about.
I used to live about a mile away from these two towers. I had the opportunity to talk with the crew when the north tower was being constructed. They were camping out overnights at the tower and I learned quite a bit about their process. I also learned what a BIG gin pole looks like, compared the little u-bolt and pipe thingy I helped my buddy with on his amateur radio tower. I am very grateful that these high intensity strobes are reduced at nighttime. I remember when these ones underwent a burn-in period and operated at full intensity continuously for around a week. The flashes made it difficult for me to get to sleep at times. The intensity required for daytime visibility is pretty amazing.
Good Day. Excellent. Some of which I know and I learned some new things. Thank You & Best Regards.
Over 20 years in the Tower industry participated in plenty of stacking/microwave/cellular…still climbing at 56 ❤ it!
Where are you based out of?
Good video. I worked in two-way communications for years. I still learn stuff!
The FAA rules on tower paint don't specify color other than red. Most are painted aviation orange. Which looks red. If the tower is on a flight path and over 200 feet it must be painted and lit. The rule is 7 bands with red at bottom and top. The beacons,( flashing lights) must be red at night and white during the day. The non flashing lights in between the beacons are side marker lights. Beacons must be 200 feet apart.
What they need now is a DJ monitor, that sounds an alarm when the DJ falls asleep.
We have a gentle alarm in our NOC, but if they ignore that for too long a loud piezo beeper kicks on.
Can't remember the last time we had jocks. All server based playout including intros and patter. Sigh.
I was a geology student at Caltech and the 1992 Landers earthquake happened during my summer research fellowship. The surface rupture went right between the legs of one of those giant electric power towers. Peak horizontal offset was 18 feet and somehow miraculously THE TOWER DIDN"T FALL!!!
Whoa!!!! That’s wild!!!
Fantastic...that answered many of the questions I had with radio towers. 😊
I might be doing some maintenance on an LP FM antenna. Is there any danger whatsoever in maintaining one of these?
It depends on where the antenna is located. If it’s on a tower more than a regular ladder or accessible from a bucket truck then I’d hire professionals. Just be sure the station is off before you get close or touch the antenna.
LP is just 100 watts But lock it out it can give you a nasty jolt our AAARRRGGGG one is 150 watts
I work with industrial machinery. You take lock out tag out to next level. I used electric fence for years. I'd scan the AM band and listen for shorts to earth. I've been that path for electric potential, not fun. I also use our radio tower local, as a land mark looking for the lights.
Interesting information. I was really wishing to hear about radial fields around the base for Medium Wave though.
I’ll be sure to ask when I talk to an AM expert (someone with many many many more years of AM experience than I have).
Very informative video...any HAM RADIO oprs on this site?
I am! Not active right now…
Fascinating. I grew up in the 50s and 60s and got my ham license then too. Where I lived in Central NY I could see newly constructed TV towers from miles away with the blinking red lights and often wondered how in the hell they built that thing because it wa the tallest structure around. then I wondered about the feed lines to the tower being that TV frequencies are shorter than AM and FM , where in the tower is the feed point? How is the tower fed especially with all that cabling that would reduce power by reactances? It must take special feed lines doesn't it? Much to learn here...Thanks
Worked ground level at many antenna sites. Been there during lightning. Is it safe or more dangerous to be in the vicinity of a well grounded tower. Versus the open field
That’s a good question. I would think a little safer because the lightning has a path to ground, but I’d still try to stay inside a building or shelter than at the base of the tower.
When I was a student at Cal Poly San Luis Obispo back in the early 1980’s, I was a DJ on the school radio station my senior year. There was a small hill on the east side of the campus called Radio Hill. There were two radio antennas, one AM antenna for a local public station, and an FM antenna for the school radio station. The AM antenna was rather large and very prominent. The school’s antenna which consisted of a wood pole with a stick antenna attached to the upper part of pole, was barely noticeable to anyone viewing it. The station at that time was only 2 kW. Most people assumed the large AM antenna was for the school station. The school antenna has since been relocated to the top of Cuesta Grade, at the north side of town. I’m not sure if the power was increased, but the service area extends like 30 miles from antenna out. The signal from transmitter to antenna back in the 1980’s was carried by two telephone lines for the stereo broadcast. As part of our DJ training, we had to know FCC rules and regulations in running a radio station as well as handling EBS tests and events. We were a secondary radio station in the case of an emergency for our service area. Each trainee who became a DJ also had to apply and receive an FCC license to operate a radio station.
We used to climb those in my youth. The ATT long lines had tons of microwave antennas in horns or "drums" That if you stood of in front too long you would get a head ache any candy in your pocket melted and the fun part of having you nose and ears bleed and one time my friends eyes bleed, but not really any pain. .
And that is why we have radiation exposure limits now.
Have you experienced any side affects of doing that when you got older?
Like coming down with cancer.
Nope. Non ionizing radiation.
Same reasons we wouldn't test/turn on aircraft weather radar on the ground, when anyone was in front of the aircraft.
I recognize the two towers at the beginning of the video. They are 20ish miles north northwest of Denver International Airport. Towers can actually be difficult to see from the air, they can blend in with the ground under certain lighting conditions.
Yep! Ended up being a really nice day.
You have to be carful with the county road to access those towers as it can get quite muddy as I discovered. I stopped by there once (from road) when in town, and was heading up to Berthoud to visit my brother and had always seen these towers from I-25 nearby. One of them is KDEN-TV and the other is a KKSE-FM "Altitude Sports" Coordinates of KDEN tower 40°05'57.0"N 104°54'03.2"W at 1243' above ground. Nearly all Denver metro stations are on Lookout Mountain near Golden.
@marcusdamberger That Lookout Mountain TV site is amazing!
Yeah, I have no illusions that my Subaru would do all that great in mud.
Very nice and informative
As an Extra Class HAM this stuff is cool…great job…if it paid more I definitely would have gone into broadcast engineering…I went to school back in the early 90s and worked on my doctorate in the mid 90s…but have and still am volunteering for our local public TV station …I use personally a large telescoping antenna (12 meters) because I’m mobile most of the time…
How TH-cam didn’t recommend this channel is beyond me. When a local cell tower was being built close to my house nearly 20 years ago, I’d go over at least once a week (I’m 39). I got to know some of the tower crew, and shed engineers. Sadly I never kept in touch much. But I still will stop at the tower if folks are working on it, and ones near by it too.
Most of the times, they’re willing to share what they’re doing. I know I was any time I had anyone ask what I was doing.
@@TheBroadcastEngineer They seemed to enjoy sharing their knowledge and experience with someone also interested in Radio Engineering. Nice to know they’re not the only ones. :)
We get pretty lonely on the road. Most of use travel a couple weeks straight at a time fixing towers all across the country!! Just don't catch me on the last day or two, way too exhausted to entertain or talk 😔 normally we climb at least once a day, sometimes 2 or 3!
@f1vet930 that’s a long stretch!
At 6:48, why did the red flashing obstruction light above your left shoulder stop flashing?
I’m thinking you’re meaning a bit later on when it’s dark. I couldn’t get the whole tower in frame. Those are the side markers.
Sorry, I meant at 8:48. I didn’t notice anything change aside from the flashing light disappearing.
There's no light above HIS left shoulder, but there is one above HIS right. Good grief!
Close caption made it read guidelines and not guy lines hahahaha
Ha! I didn’t go though the transcript. I forget to check that sometimes.
Why isn't it "guide" lines?
@@rudolphguarnacci197 Why is there nothing loving or joyous about a "lovejoy?"
@@whuffer5103
I give up, why?
4ôúř Eié Dothé Thinqué tis from ye days of Olè Whencé French und Dutch Windjammers did use such Ropes to stabilise Thiné main Mast
front range, what station?
@15:28 ...are these ground balls also known as Corona balls....I'm waiting for Alex Baldwin to tell us about his "Schwedde Balls" from SNL
😂
The safest place to be during a thunderstorm,( if you have to be there at all) is on the tower away from the bottom and top. The tower has a faraday effect letting the lightning go around you to ground. More than once I've had to move to the middle of a tower, belt off, cover my ears and wait it out. Iv been essentially struck by lightning dozens of times because of this. At the top you become the lightning rod and at the bottom it can arc to a good conductor which being mostly water you are. It's actually safer to be on the tower during a thunderstorm than it is in the equipment shelter even though the transmission lines have lightning arresters because occasionally there are strikes that exceed the limits of an arrester enter the equipment room. But no matter the power of the strike the tower just takes it around you safely to the ground network. When establishing critical path for a tower site lightning is an important factor in determining whether grounding should be before or after erection begins..
What besides space determines the maximum angle of the guy wires?
Very interesting,here in Ireland,the lights flash at night, theyre red, and the two other lights in between are red but steady
Yeah I didn’t cover that as in detail as I could. But yes top lights flash and others are steady.
@@TheBroadcastEngineer you covered it well it was very interesting, can you do a video sometime on what the power of the signal does i.e when they say the signal is 160kw or 5 kw, and what the advantage of height does, not only by being on a mountain top but the way national tv and radio tends to be at the top of a mast and the local station ( at least here in Ireland tends to have the radome or antenna nearer the bottom, that would be interesting ( i meant megawatts not kilowatts) 🫣
Thanks Marcus, and as well that often towers also carry lots of other services on them, so climbing them more than a foot above the ground also requires that the other co users also are notified, and that they also safe their equipment. especially true for climbers, but even you could be just on the base connecting a new cable to your side, and the RF is not the greatest thing to have.
I’ve never had an RF burn, but have seen some people who have. I’d prefer to refrain from experiencing that.
In the 90s a small tornado hit cedar rapids Iowa and felled a 400 foot guy tower across the parking lot and back of the building where they made universal gym equipment. 15 cars were flattened and 2 people were killed. We had to go and move the mangled tower to a nearby field and put up a new one. Start to finish 6 days.
I worked somewhat near a series of tall transmission towers well fenced in without much built up around them. I had a coworker who grew up closer to them, and who said sadly that she’d watched one tower fall during the build. She reported seeing workers fall, apparently not tethered, not that it would matter at that moment… We also had railroad tracks by the worksite, and a switching yard was almost in the backyard of her family home. One day early in my employment at the job I commented upon the series of black painted rail tanks rolling by. My coworker asked if I knew what was in the tanks. I hadn’t read the white lettering, and stated that I didn’t know. “Anhydrous ammonia. That stuff will burn out your lungs if the tank leaks!” YIKES!!
Only decades(!) later, after thousands of those A.A. tank cars had creaked past the facility the employer instituted safety drills in the event of a rail accident; where to go, what to shut and shut off, who to call, etc.
One thing noted about the antenna guy-lines are the weights riding upon the lower limit of the cable before they terminate at the anchors! We have snow and ice here in winter. Obviously there is much wind at heights. Temperature contracts and expands material. I have long wondered how much “give & take” any particular guy line is subject to!!
Great episode!
@williesnyder2899, the guy wires are almost completely inelastic. They 'give' a bit under gravity and dynamic loads such as wind, ice accumulaton or seismic activity but, essentially, do not 'take' to return to original length or tension. From time to time they need to be retensioned properly to maintain the straightness, vertical alignment and overall structural integrity of the antenna system. Not unlike tuning a stringed musical instrument.
In college I remember a large FM broadcast tower that fell across the street from my dorm. One moment it was standing up, then, it was gone! Someone had cut a guy wire and caused its collapse.
Yikes! There are those people who just want to watch the world burn. And towers collapse.
@@TheBroadcastEngineer It was the KANU tower in Lawrence, KS. I think it was in late 1982 when the incident happened.
Very interesting information for a lay man.
I live over the big pond in the UK.
Near my locality is a Tv/radio mast called Winter Hill just outside of a small town called Egerton.
There is also a aircraft crash site a few hundred yards away.
The aircraft did not strike the mast but I believe it was bad weather that caused the incident.
You learn something every day.
Thanks for the great video 👍
I lived in the UK for about 5 years, first in Manchester, and then up near Blackburn. Winter Hill was an impressive transmitter tower to see, it was huge.
When I was in electronics school back in the 80's I learned that TV broadcast was done through a port-hole from a tube. I also learned that CB radios don't have much power on their antenna when under broadcast but no voice. Start speaking and the wave peaks around 400V. That'll brighten your day!
At the previous job, the old main antenna’s “tower” was actually the antenna for on old TV station.
I went to DeVry in the late 80s. It was a great school. I went there because of my interest in all things radio since I was a kid. AM, FM, CB, etc. transmitters, receivers, amplifiers. Still have a fondness for it all. Wish I could put my interest to good use.
Worked at an electric company and it was frustrating that the orange red marking paint would fade and need repainting every 10 years. Bad enough to do it once but worse over and over. There was a color chart to see if it had faded.
I didn't realize that AM radio towers were that dangerous! Good to know!
I do have a question, though. The RF energy being transmitted at a radio station, can it have negative affects on the human body when one is very close to them while they are operational? For both AM and FM. I know microwave transmitters have the capacity to cook a body like our home microwaves do for our food when one is in direct line with the antenna, but I am curious if that is possible at AM or FM frequencies.
It’s all about wavelength and resonant frequencies with body parts. At AM frequencies not really an issue. FM frequencies will cause heating effects on some smaller body parts.
This is a hotly debated issue. It's called the effects of non-ionizing radiation on human tissue. Non-ionizing radiation is basically radio waves versus ionizing radiation like X-Rays, and radiation emitted by radioactive material. There is some evidence that children living under high tension power lines have a greater likelihood of developing leukemia than those that don't. Yet the people that work on those power lines seem not to be affected. Microwaves are kind of on the dividing line between ionizing and non-ionizing radiation. Some people think holding your cell-phone close to your body, especially your head may make you at higher risk for certain forms of cancer. Some people are really concerned about 5G cellular, since those towers have to be much closer to the user than the older technology. Now, having said this for every study that says there are these negative effects, there is another that says no, it's perfectly safe. Marcus is right, do not ever touch an AM broadcast tower, ever. I've drawn electrical arcs off the guy wires at an FM tower just running a screw driver over it. It could have been from static electricity and the place was pretty hot with RF. There were two FM stations on tower, and the NOAA Weather Radio Station, but it's only 250 watts. I've been messing with RF since I was a kid, I'm a grandfather now. I do maintenance on some Ham repeaters. These are located in areas where there are broadcast transmitters, cell phone systems, and other transmitters. I've been very close to a TV transmit antenna, and had my face inches from our own 120 W VHF transmit antenna. I developed cataracts when I was only 40. Did this behavior have something to do with that? I don't know. My doctors think they see some changes in my optic nerves, however my distance vision is still very good. So, they keep poking and prodding at me, but still no definite answers. I do know this for certain, the FCC and the EPA are now making us answer questions about RF safety on the Ham tests, and we are supposed to do an RF safety evaluation on our stations. Even though the highest power level we can run is 1500 watts PEP. Most of us on our VHF and UHF stations seldom exceed 50 watts if that much. Pretty tame compared to broadcast transmitters. We once asked the engineer at a 50 KW AM station, what happens if you touch the tower while standing on the ground. His answer was, "you will disappear in a pink puff of smoke." Something like that happened to a would be copper thief at another AM transmitter site.
I wouldn't want to get a serious RF burn....I'm theorizing that there is enough current at a 50kW AM radio station tower. I wouldn't want to be these foolish Russian teens: th-cam.com/video/b9UO9tn4MpI/w-d-xo.htmlsi=x_M_tYHEk82dY6gD
Some towers are both AM and FM. The FM antenna will be mounted at or near the top.
Fascinating topic. Thank you
Those balls at the base of the antenna were called "Johnny balls" by old-time radio engineers.
I am a recent convert to DXing, mostly AM radio. I have begun to notice every tower I see on my truck route along coastal South Carolina. I never realized the complexity in a tower structure nor the challenges that must be overcome to maintain its integrity. How tall can a tower be erected without use of a sky crane helicopter?
I would guess that it would depend on the tower crew building the tower.
1) Electrocution implies death. Shocked implies being in the path of the electrical current.
2) Not all AM towers are insulated, thereby "series fed". Grounded AM towers are "Shunt Fed". They are excited by a sloping line up to a certain point on the tower. They are relatively safe to touch, but as you say, you should not be there in the first place unless you are an authorized professional with an official reason to be there.
3) Towers are by regulation enclosed with a safety fence for a good reason. If you think you need to be inside the fence, most likely you don't Consult the tower owner or operator and explain your needs. That's a good way to get shocked, burned, have things fall on you or even encounter fast moving articles made of lead.
-- 62 year Consulting Engineer, Broadcast engineer, tower climber. Retired, Denks Gott.
Question about what you said when using standard vehicle jump cables to ground the antenna…are you saying the balls you would hook one part of the cable to doesn’t hold electrical currents? And obviously do this when the transmitter is off. I had to rewatch that part a few times to understand it how to ground the tower. You said connect end of the cable to the tower itself then the ball. You had also talked about how a tower can also be a good receiving antenna and currents still be carried if that tower’s transmitter is off completely if I understood that correctly.
How is it that when connecting a jumper cable to a bare metal part on the bottom of the tower still couldn’t carry electrical currents and one not get electrocuted?
If you look at the balls, one is connected to the tower and one is connected to ground. You basically want to jumper those together without moving them. You're just grounding the tower. Yes, you want to have the transmitter off, otherwise, you could risk damaging the system.
The specifics of how to short a tower are probably best not explained in a public forum like TH-cam for safety and liability reasons. People who have intentions on climbing without permission or training might think they know what they're doing and get it wrong. Most likely ending in a fatality.
Cool. Thanks for sharing.
The guys are there to transfer lateral movement into vertical. Think about a right angle triangle rotating and it becomes clear.
Very interesting. Very well presented.
Excellent video!!!
Lots of AM broadcast towers are also the supports for multiple unrelated and electrically isolated antennas.
Some are yes. But it’s more the exception than rule.
Guyed towers are pretty common in the world, here in europe there are so many, in poland many over 300 meters tall and in france, germany, UK a few taller than 300 meters.
I once soldered on a live AM tower, on purpose. Granted it was a shunt fed tower, and it was only doing like 1kW.
I have a quesion and a suggestion.
How do AM stations change their daytime/nighttime patterns? I'm guessing that it's done with relays to specific radials.
I also watch another TH-camr, Jeff Geerling, He does a computer oriented channel, his father is, or was, the engineer for KMOX in St Louis. He had an interesting video of some of the KMOX radio transmitter equipment. Perhaps you could include him in an episode.
Directional AM stations have at least two towers. The output from the transmitter goes into a "phasor" that controls the amount of signal that goes to each tower and the phase between each. If you did any vector analysis in trig class, you will recall that different signals will add and subtract with time. This translates to more signal radiating in some directions and less in others. When a pattern change is done, relays do change between the controls for the daytime and nighttime pattern. Sometimes, even a tower or two are energized or de-energized depending on the need. I used to work at a four tower directional station but we only had one pattern. This was in the 70s and stations had to keep a first class licensed operation at the transmitter. There wasn't much else to do, so I manually calculated the patterning using the information from the phase monitor. I used an add, subtract, multiply, and divide calculator and a slide rule for the trig functions. It was necessary to calculate two patterns using two towers then use those figures to calculate the finial pattern. Signal strength was calculated at 10 degree increments. Imagine my surprise when I plotted the pattern and it came out reversed. I missed a sign somewhere. It was a good exercise, but I didn't do it over.
@@michaeldaniels3639 thanks. Yes, I'm acquainted with a phased array antenna from my amateur radio hobby. I was unaware that AM stations use multiple phased towers. I was guessing that it was by using relays to activate / deactivate ground radials.
Very interesting 🤔 thanks ❤
My first BASE jump was off of a tower-1250’agl.
My first night BASE jump was also a tower jump-900’agl.
I can’t drive past a tower without looking at it and accessing it’s “jumpability”.
Haha you're crazy! No thank you! :)
Against my best advice, my friend touched an energized one of the two WIP am towers at their tx site in NJ. We had to call an emergency squad from Westville to keep him alive. Fortunately he learned his lesson. I keep telling people to just stay away from these places! Look but just don't touch!
Wow 8 hundred thousand feet tower. That's huge.
Thanks for the great video tho. I don't know why but towers that are higher than a certain amount scare me. I can be mikes away and just looking at them they freak me out
Yeah. He misspoke several times.
Damn, your audio is great. Thank you.
Interesting. Thanks
Thanks for the video I always wanted to build a radio tower maybe you could tell me some tips to build a model one I'm making a small model one so I know what it looks like in the future
That's cool! I unfortunately, don't have any tips for making a model version of one.
ok
What scale model and what are you using as a media like toothpicks or model car sprue. Also what type of tower are you building, self support, guy tower, monopole, horizontal billboard?
@@dansteel9873 toothpicks and chopsticks that are connected with hot glue and the tower is self-supporting and I decided it's a cell Tower
I don't know where you got 800,000 feet tower but no. The maximum height in the u.s. is 2000 feet of tower and there can be up to 200 feet of antenna on top allowing a 2,200 foot maximum to the top beacon. In Russia there were a couple of 3000 foot towers but one fell leaving one.
I don’t know where you got 800,000 foot tower from…
Why do towers start fires when they fall
Most of the time they don't. If they do, it could be from friction and sparks as the tower collapses and falls into dry brush.
What about Shortwave radio antennas?
What about shortwave antennas? Shortwave broadcasting isn’t very big in the United States, so I didn’t cover that.
@@TheBroadcastEngineer Its getting bigger again WRMI Legends on 5050 & 9455 kHz, WWV & WWVH 2.5, 5, 10, 15, 20 & 25 MHz, WWCR 3215 & 4840 kHz, WTWW, 5085 kHz & WBCQ 15420, 9330, 7490, 5110 kHz to name some as well as many overseas.
@@drsysop I'd imagine that since they pose the same danger to aircraft, that they also would fall under the same FAA regulation.
Have you been following the missing tower at the Alabama radio station? Any thoughts about that?
I have! I’m actually recording a video today about it pulling together different sources. It’ll post tomorrow.
@@TheBroadcastEngineer look forward to it.
Ive been building towers for 30 years and the most terrifying task of them all is changing out guy lines. I know of at least 25 men killed on tower sites from the tower collapsing but not a whole lot of straight falling themselves. Im hoping to never be on a 1000 footer that collapses.
That is one of the most terrifying things for me as an engineer too. Even though I’m not performing the task, there’s so much riding on that.
@@TheBroadcastEngineer Senior Rd tower collapse back in 1982 was one of the worst Ive ever seen. Not sure if the video is still up or not.
@gregoryrobertson6866 Yikes! I haven’t seen that one. I’ve heard the stories of the two KFI collapses.
Make that three (aux went down once too).
The Tower !!! The Tower !!! Rapunzel Rapunzel we're going to the tower !!!
Shirley, you can’t be serious.
@@chuckinhouston9952 Shirley is an entirely different person from me , all together.
Nice Job thank you for your hard work 😅
Nice topic
Laying on top of an old Western Electric KS-15676 horn antenna while looking at the summer night sky. Was always worth the horrifying 250' climb back down. 🛰️ ✨ 🌖 ✨ 🪐 🛸
The question of can radio frequency radiation commonly known as RF Cook a person. You betcha. I was putting a quarter wave dipole up for an FM station in Orange California and setting azimuth was a challenge because up there there is nothing to push against so I got between the antenna and the pole it was mounted on and immediately felt my body get hot from the inside. All RF is dangerous depending on proximity and duration and power level, regardless of frequency. If you were to get in the path of a 2 gigahertz studio tower link for TV you would be fried just the same as walking up and grabbing an am tower. Occasionally it happens that birds will fly in such a path and zap. They don't explode or go down in flames but they do literally cook on the inside and fall out of the sky. RF radiation excellerates the water molecules the faster they move the more heat is created which is why some things can be cooked in a microwave oven and some things shouldn't. Objects with no water molecules like foil repel radio waves that's why foil sparks and can ruin your oven. It reflects the power back into the transmitter kinda like if someone were to shoot at you with a laser and you put up a mirror and bounce it back at them.
Why was the station on while you were climbing to adjust the antenna?
What kind of engineer are you? I feel like there's a lot of "creative freedom" in the information presented here.
Such as?
Maybe consider facing an alternate Direction during your introduction because there's a massive shadow distracting from your face. Maybe gets a reflector to light the other side of your face. Your eyes are shrouded in darkness
And then there are the _ham_ radio towers.
Who can a civilian call to report a tower light out? One of the local radio stations (FM) has the top light out. Middle is still flashing. I used antenna search to find an email address. I sent an email telling them. It's been over a month. Light is still out.
You can call the FCC and they’ll send some nastygrams to the station.
@@TheBroadcastEngineer I bet they know the light is out and just don’t want to hire a climber just to change a few bulbs. Most white lights come with multiple bulbs that will switch when one burns out. Flashing beacons are a special type of light, expensive. Red light are out of style. Some people have a nervous reaction to red light, strange but true.
I went back into the woods after they put a new tower up and i found a red Pyrex glass light cover laying in garbage that had been left around
Often times we do LED upgrade installs, normally the guys will toss the beacons/side markers off the tower to save time and energy. Some of the older incandescent stuff is pretty cool, I collect a lot of the stuff we decommission and re engineer with LEDs for home display/entertainment purposes!
@f1vet930 I came into possession of a side marker. It’s a cool little display piece.
When your message cannot get corrupted .
As growing up as a tower. I can confirm this video.
😂
Scary
?
@@TheBroadcastEngineer crazy heights
Ahh. Yeah, I’m good keeping my feet on the ground.
The FAA will not take a notification of a non lighted tower from anyone other than the tower's owner. Check your maps for towers and don't trust that they are lighted at night.
If it’s a complaint instead of a NOTAM notification, they’ll take the complaint.