2 Meter VHF Quarter Wave Ground Plane Antenna - Ham Radio Q&A
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- เผยแพร่เมื่อ 28 ต.ค. 2024
- Are you looking for a fun and easy antenna project? The 1/4 ground plane might be just the ticket. This particular ground plane is constructed out of an SO-239 chassis connector, so the radiator is attached to the center conductor of the connector and the radials each come off the base.
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Hi Michael. The first 2 meter base station antenna was that antenna, up in a pine tree. I followed the ARRL pamphlet I got as a new ham. I only had 2 ground radials and the instructions called for a loop in the wire ends, formed by wrapping the end around a broomstick. I still use that antenna.
It doesn't get much simpler than this antenna. It was my first one also. I think I used the same plans from the ARRL. Back in the day at one of my previous employers, I had a two meter base radio on my desk. I stuck one of these antennas up in the suspended ceiling- it fit perfectly and worked great.
@@funpotatoman It works in the 2 meter band and the 70 cm band as well. Hence the title of the video :P
I made this antenna 3 years ago after watching this video. It was easy and super easy!!!
If you are thinking about building this project, just do it. It is easy and works great!!
Awesome, as a new ham I will definitely be making this. I wish some store locally had SO-239 connectors. Wish Radio Shacks were still around. 73 - KM6VFM
Congrats on getting your license. Radio Shack was great for parts when you wanted to do a little project. Another option may be an electronics store like Ham Radio Outlet or Fry's. Otherwise you can order the SO-239 from Amazon, there's a link in the video description.
Radio shacks are still around in 5 land.
We used to have an excellent parts store near us called "Unicorn Electronics". You could get everything there! Unfortunately, COVID ended up being the end of them. I dearly miss them!
I Agree! I Wish RADIO SHACK Was Still Around! 🇺🇲
I’ve watched this video a couple times now and finally got around to making the antenna this weekend. Wow! Super easy and quick to build. I wanted to get it built for the 2M Simplex Light up the night event on August 30, 2020. Can’t wait to use it.
This was exactly what I was looking for to do my first antenna project for being a new ham. Thank you.
You can also get SO-239s at Radio Shack. I just passed the test for Technician license and while I wait on my license I am making one of those 1/4 wave ground plane for the 2 meter HT (Yaesu FT-4VR) mono band radio I got from the local Ham club for passing the test. I can hit the local 2 meter repeater but that's about it and I have to be outside on the deck to do that. I think once I get my 2 meter ground plane built and get my SMA female adapter to UHF SO-239 so I can hook up a piece of coax I'll be good to go. Since my wire is so thin, I doubled it up and stuck it into my drill and twisted it all together for the radiator. That worked out well and now it sticks straight up without drooping.
So easy an effective Michael, definitely going to build this! Thanks for sharing in such easy steps. 73
I needed a 2 meter ground plane quickly and didn't have time to muck about trying to optimize a fancy design. I just copied yours and it works as well as anything I could have made if I had taken much more time to make it pretty. I just cut and bent and soldered per your design and presto, it works great. SWR about 1.2 across the band and I'm easily heard where i need to be heard. Thank you!!!! 73
You can put one end of the wire in a drill chuck and the other in a vise. Straightens it out and makes it less prone to bending
Just built one. Works slick! Also I built another 2m antenna using just the 19 in vertical radiator soldered to an SO 239 connector. That one also worked well. It stuck it in the attic
I don't have my license yet (local governing body suspended examinations due to Covid19) but I built this for listening and it worked like a charm.
Wow. Awesome SWR. No tuning either. Personally, I would like to see more videos like this. My favorite was the Leixen 10w Radio in a Ammo Can. Built one myself.
Thanks for the comments. The project videos tend to be popular, so I will add more the mix.
Soon to be new ham operator, saw this antenna, took down lots of notes. Video was VERY informative especially the formula aspect. Thank you for the video. Gonna give build a try, should be fun.
The SO-239 that I got from HRO didn't have a good mechanical connector for the center solder point. I was more like a dimple with half a side. What I did to strengthen the connection was wrap some 14 gauge wire around a #6 screw, to get a coil about 3/8" long, nice and tight. I placed that over the center connector and filled it with molten solder and heated it enough to know the solder point was well connected, then embedded my 12 gauge center wire in that and heated it again to get a good solder connection. That joint is not going to fail.
Great little project for new and us old hams. Made one for 70cm and works great.
@@th3wr3ck Hi, from memory about 1.2:1 in our repeater allocation.
Hi Michael, thank you for sharing what can only be described one of the easiest but useful little antennas inexperienced amateurs like myself can build. I have built a similar type of antenna for portable days out but I used a slightly different calculation which offered me a slightly longer radial (2948/Freq = length). I note that my swr is slightly higher than yours so maybe I stick with 234/Freq. Thank you for sharing. M6KVK
It's because you didn't take into account the 5% "loss" in the speed of light or radio wave. In a vacuum or in outer space, that 2,948 applies, but in the real world or on Earth, there's some "absorption" of some sort. If you multiply the 2,948 by 0.95, you'll end up with 2,800. That's the right one.
I built one of these a couple years ago, slightly different than your video only in that we had extra PVC parts so we could take the thing apart and store it in the PVC to transport. Otherwise, it looked the same and is a great antenna.
This was the first antenna I made.I was able to hit a repeater over 40 miles away with 5 watts !
Hey thank you for this. I built something very similar after watching your video but much less "professional" so to speak, by sticking a 12 gauge copper wire into a female pl-259 connector and wrapping the radial wires around the outer part.
Thank You. This is exactly what I need. I'll be sourcing the parts soon and put this baby together. Thanks again.
Just made one of these antennas a little tip i got from a elder is to put one end of the wire in a drill then hold the other with pliers. Give it about 10 seconds. It straightens and strengthens
For us unlicensed radio hobbyists, cut approximately one inch form the vertical antenna to be able to use the ground plane antenna on unlicenced MURS VHS frequencies. MURS is on the 1.9 meter radio band. It is very close to 2 meter amateur radio band. Many amateur radio frequencies have unlicenced equivalent bands for unlicenced radio hobbyists and operators. 12 meter and 10 meter amateur radio bands are very close to the unlicensed 11 meter Citizen's Band. 6 meter amateur band is very close to the unlicenced low power 49 megacycle band. The 49 megacycle band is actually in 6 meters whereas the amateur radio 50 to 54 megacycle band is actually 5.8 meters. 2 meter amateur band is very close to the unlicensed MURS band that y is in 1.9 meters. 70 centimeter amateur radio band is very close to unlicenced FRS 64 centimeter band. 33 centimeter amateur radio band is shared with unlicensed radio operators also that use equipment that is low power and requires no license. I believe all these frequencies for unlicenced use are around amateur radio bands to stimulate interest for us unlicenced operators to perhaps get an amateur radio license.
Just built this antenna and it works well! It also picks up 70cm too. Thanks!
You can build all of it with crimp connectors and a coat hanger or two if you want, use quick disconnects for the antenna and ground plane and you've got yourself a modular antenna
Hi Michael!! I just subscribed and
I'm proud to say I'm subscriber
number 8454!! I look forward to
watching your videos and learning
ALOT from you!! Thanks for
posting and giving us all a chance
to learn and do it right. Norman.
Thanks for coming along for the ride. If there is a topic you want to know more about, let me know and I'll add it to the list of future videos.
I did this quarter wave ground plane antenna here in Philppines connected to SO 239 connector Radiator lenght 19.2 inch with 3 ground plane. I used RG58 coax 50 ohms. Oh yeah IT WORKS WELL with VHF Freq. Design for 2M. - DW3ZXC Philippines.
Dumb question - Does a coaxial version of this chassis mount exist? I googled search but could not find anything. I aleady have all the connectors and tools to crimp coaxial - not so-239.
I love your mission Michael!
I would like to put a small circle in the ends of the radiator and ground planes, to reduce the likelihood of poking my eye out. How would that that affect to performance and how would I measure the length. I there something blunt that can be put on the wire ends, that would not affect the performance?
Now this is an antenna ! i still have my radio shack 20-176 aka Sputnik in the attic
Im inspired to build. Was able to pickup most of the parts at my local hardware store. cable and SO 239 connector I had to get online. the cable coax was my biggest expense RG8U. Also find the right connector for the connection from the feed to the Radios antenna connection found a SMA female to the pl 259 female(so239) ...As of now I have no Antenna Analyzer... anyday now i hope to see my call sign on the FCC post. was able to program my first repeater here in Santa Rosa CA ..listening only ..Thanks
Hello MIchael. Will be getting my General in a few days and antennas are my weak spot, so appreciate your info! Keep it up! I will check out your blog.
I foresee some father/daughter bonding with this project in my future!
Awesome! My daughter was 13 when she got her license. This is an excellent project for the two of you.
Build two antennas and mount one on the roof of your house and one on her bicycle on the end of an old broomstick. You stay home and operate the house radio and she goes out on her bicycle using a hand-held transceiver. Have her test on low power with the tiny dummy load walkie talkie antenna and then have her connect the broom handle mounted ground plane attached to her bicycle. She will see the big difference and she will learn that antenna is more important than more power. Have fun and make memories.
Went down a major rabbit hole trying to figure out why it was 234 and not 246. Great video. I'm making this tomorrow thx! If I tune it for GMRS I get 6 inches. May try for both (I have both licenses.) Thanks!
Thank you. That was quick and well done.
That was my first home brew antenna. N0QFT
Might hobble one together for Field day! may need to use 1/4 or 1/2" copper piping on the main element as I am trying to feed it to an IC746
Excellent video - thanks. It's stuff like this that makes me love HAM radio.
I enjoyed this video - i only operate in 80, 40, 20 m but I want to get a 2m radio and have been looking for ideas on homebuilt 2m antennas
Thanks for this video. Does it matter when the elements are not totally straight? :)
First antenna I built after I got my technician. Got it out of the ARRL Handbook. Not do sure you can get the SO-239 and other parts from Radio Shack.
Back when Radio Shack was around it was super easy to pick up on SO-239. Otherwise here's a link to where you can pick up a couple on Amazon: amzn.to/2wcEPkp
I want to build an antenna like this for my SDR tuned for the airband. I have a question: Can I replace the SO-239 chassis connector for a BNC connector?
This is incredible! Any reason it wouldn't be water proof for a more permanent outdoor install?
Disregard! I found your response to a similar comment below
Can you do another talking about the cable you used? You kinda skipped over that completely. I know I will need a female SMA on my radio end and a male PL239 on the antenna end, but what type of cable do you need? How much loss do you get going from 12 feet to 50 feet for example?
Hi Michael!! I've got a topic for you:
different materials for antenna
building, ie: copper vs stainless steel vs aluminum;
wood vs plastic vs pvc.
Different conductive properties of
each, strengths & weaknesses of
each, etc. What do you think? Are
radials, radiators & ground plane
wires better in copper,
stainless-steel or aluminum, and
why. Also: can we mix them? I
would love to see THAT video!!
I'm sure you could produce a great
video on all that!! At the beginning
of the video don't forget to
mention who the inspiration is
behind that video!!😉. It might just
inspire others to come up with
other good ideas!! I can't wait to
see it!!
Keep on keeping on, brother!!
73, Norman in Montreal.
Great video !!!!! thank you, but what would be your take on the voltage output, in other words would it handle 200 watt PEP ? thanks for reply in advance, Please keep the videos coming!!!
I don't see why not. Back many years ago we made some 1/4 antennas like this for some APRS digipeaters that were running on 110 watt GE Delta land mobile transceivers. Didn't have any issues at that power level, so 200 watts would be fine.
I just made one having followed your video. I’ve just got to come up with a mounting solution. Thanks.
Hi KB9VBR, in the most simple way, how do I make a quarter wave ground plane (receiver only) antenna for aviation frequencies 108-137 MHz ? Thanks and hope to hear from you soon.
Awesome kool project
Thanks for sharing. This might be my first project. 73
Great Video... New to amateur radio VA3MFP Just got my license 5 days ago . Looking for a basic antenna until my Diamond Antenna X30A Dual-Band comes in.
So I made one and it keeps blowing the circuit breaker as it's transmitting. Should I run a wire from the SO239 to the wood base for a ground?
This video is a must see for new hams great simple explanation. 73. David Byrd KN4BHS
Hi, with my intentions to only receive aircraft & tower communications within the air band frequencies 118.000 MHz to 136.975 MHz, I need to make an external antenna for my scanner. In determining the length of the vertical rod and redials, will I still use the given 234 numbers? If so, what MHz frequency will I divide the 234 with?
how about improving an HT antenna by having a base loading coil, cant find any good info on that process. 5/8th wave loaded
Excellent video. How well would this work indoors?
how come you not add the short to ground i seen them the antenna wire solder to it and that wire solder to the ground plane kit you have do one this way see if you like it even better the short kill static DC building up in your area
That’s a real nice and simple design, I’m going to build one, thanks!
It also works for the 70 centimeter amateur radio band as a 3/4 wave antenna. Unfortunately, the radiation angle for a 3/4 wave, 70 centimeter band antenna is very steep. This will make for more limited horizontal range. For satellite and near repeater use, it will work and have a low standing wave ratio.
Nice easy build, how was the Db gain
?
Outstanding video tutorial. Thanks for posting. Much appreciated.
I have made the 2m 70cm, my problem is I can’t get the solder to adhere to the copper wire and the so239 connector. So the main beam is the 2m, and then I attach the 70cm beam next to that. Can I move the 70 up a little bit to have its own connection to the 2m beam instead of having a big blob of solder at the 239. Like I said above need some direction to get the wire and solder to adhere to the 239 and be secure. Thanks Michael
I like this project because it's cheap to build. New to the hobby. My two questions. If its outdoors what do you use to keep the rain out of the connector? What about lighting protection?
For weather protection I'd use a high quality electrical tape, Coax Seal, or better yet, amalgamating tape to seal the SO-239 connector. If you are going to use the antenna indoors, like in an attic, then tape isn't necessary. As for lightning protection, that's a big subject, but in a nutshell I'd recommend lightning arrestors on your coax where the cable enters the house. The arrestors can then be grounded for lightning protection.
Thanks for the video, very straightforward. I'm hitting multiple repeaters. Coax is tape wrapped and runs through a pvc pole. Have tighten nuts on radials, but they have a tendency to sway with wind or other movement and need to be readjusted. Saw the comments on silicone sealant to help weatherproof. Should use the silicone on the soldiered point, well as as the radial connections to help stabilize and weatherproof? (Also a proud owner of your break-away copper j-pole).
You can silicone all the exposed portions of the connector (with the exception of where the coax cable connects) if you wish.
Thanks for the video! I built one but the radial ring terminals seem a little weak, they don't seem to hold the weight of the radials properly. I've seen some people go out about an inch before starting the 45 degree bend; if I were to do this, does the measurement of the radial begin at the point of the bend?
New ham here. Would this work to lengthen all wires to 3/4 wave on 2m (around 1500mm) so I could use it as a 1/4 wave antenna for 6m (also around 1500mm)?
73,
KK4FVZ
Great tutorial and demo, thanks!
Thank you. I'm trying to make one for my marine radio. I'm assuming I just need to make sure the length of the wire is right. I also live in the Milwaukee are and I plan on getting a ham license.
Yes. This design will work for the marine radio band. Just use the formula to determine the length of the wire based on the frequency you wish to use. I'd probably build the antenna for Channel 16 as this antenna will have enough bandwidth to cover the entire marine band.
Good video, congratulations from UR1CDG
It looks like an umbrella, I wonder if I could make it with one? 🤔
Thanks for the antenna info and good job on the video.
You didn't show connecting the coax cable. how did you do that?
Nice fast and easy antenna
Hey Michael, new ham here, thanks to your video you've inspired to build(instead of buy) my own very first antenna as I start to build my shack.
Question for you;
I live in an area that sees brutal winter conditions(80-100+mph winds, HEAVY snowfall). I plan to enforce all the copper elements with a wooden-dowel skeleton of sorts. Any special considerations I should make adapting this design to be more robust to withstand a brutal winter? I plan on mounting this in the very tip of a pine tree outside my window
I'd probably use brass welding rod instead of copper wire as it would be more rigid and durable. I'd also try to beef up the area around the connection with a mounting plate made out of aluminum stock. The elements of this antenna are pretty thin, so even with 80mph winds, the wind loading will be quite slight.
Question, I have a limited space, let's say I wanted to use to meet her and 10 m can The middle let's say for 2 m and then the radio coming out 10 m? Will that mess up the SWR?
Please show how you hooked it up to the coax and couldn't you simply silicon the adapter to the top of the PVC pipe?
I made one of these, works great 💪
We don't know how EFFECTIVE this antenna is if you don't COMPARE it to just using the rubber ducky. Science class 101...
In reality, almost any antenna is going to be better than a rubber duck, so I'm not sure what benefit you'd gain in showing the comparison.
Could you use sections of roll up metal tape measure for the radials and radiating element?
Would be fun to test this antenna vs your jpole.
That's a great idea. Each has their unique advantages, but an antenna shoot-out would be fun. I'll add it to the list.
Gonna try that for an FM transmitter. I did a dipole for it and it works but I wanna see if this will help any.
And yeah I'll stay out of trouble lol
Hi there.. I wanted to say that I'm a fan of your videos. I'm a fairly new ham and projects like these are just awesome. Thanks for taking time to produce these cool vids. I do have a question however, I currently have a vertical antenna for 2m and 70cm. I have it side mounded to my tower. My question is how far should it be? I have an swr of 1.3 on 146 mhz but on 446 mhz, it's an 1.8. What's your take on this?
Typically you want a side mounted antenna to be at least a 1/4 wave away from the side of the tower. Although depending on the style of the antenna, it could be closer or further. The reason why the SWR is higher on UHF is that the antenna could be coupling with the tower or possibly you just aren't getting a good tune on UHF and the antenna may require a bit of adjustment.
Hi Michael great video, can I ask a silly question please? What diameter are the blue Crimp Connectors please?
I'm not sure of the actual diameter, but blue crimp connectors will hold 12-14 gauge wire. I used 12 gauge solid copper wire in the video.
I'am curious if increasing the radiator wavelength e.i. 1/2, 3/4, 5/8 or possibly a full wavelength to the frequency would increase the gain of the antenna?
Thanks for sharing!.
For a vertical antenna, only the odd numbered wavelength quarters, and close, are resonate with an end fed antenna. 1/4 wavelength will resonate when end fed. 2/4, or 1/2 will not. 3/4 will resonate when end fed. 4/4 wave, or 1 wavelength will not resonate end fed. Of course with a some sort of antenna matching circuit, the even lengths will resonate when end fed. The odd wavelengths will resonate with no added matching circuitry. 1/2 wavelengths will resonate when center fed instead of end fed. That will be a dipole antenna
Should connections at the bottom of antenna be water sealed? Mine got rained on n seems to be acting odd..
Was wanting to do a half wave wire dipole for 2 meters is this ok or should I do quarterwave
Hey great video. Just wondering, do I need to tune the antenna to a certain frequency or will it work for all across the 2m band? I'm new.
This antenna should have enough bandwidth to cover the entire band if you cut the element for 146 Mhz.
@@KB9VBRAntennas Great thanks for the reply.
is it better then regular dipole ?
Hey Michael, I'm about to put this antenna together as you instructed. What would be the connectors needed for the RG8x coax. I'm hooking this up to my Baofeng BF-F8. Thank's for your help.
The SO-239 (UHF female) connector the antenna is based on mates to a PL-259 (UHF male) connector. Your cable will need PL-259 connectors. You will also need a SMA Female to SO-239 adapter for your radio. Those are available on Amazon: amzn.to/2XuhZ78
Would this transmit/receive any better if the ground plane was a flat (thin) aluminum plate, with a radius equal to the length of the radiating element? If so, would it make any difference if the plate was round or square?
It seems performance might be better or worse in various directions, if the plate is square. Thank you.
I don't think you will see an appreciable different between using a solid ground plane versus separated radials. The purpose of the ground plane is to provide a counterpoise for the antenna and in VHF/UHF, the number of radials doesn't seem to have a big effect. You may see a bit of a pattern change, but it won't be a big one.
@@KB9VBRAntennas thank you for taking time to share your experience.
Thank you Sir. If you don't mind what type of solder do you Reccomend. Thank you...
You should use Rosin Core or solder labeled for electrical use. Acid core or plumbers solder will break down the connections in the presence of electrical energy.
@@KB9VBRAntennas Thank you!!
This is awesome!! Thank you. Way easy
Looking to build my first antenna - just got licensed last week. What kind of coax cable and pvc pipe would I need? Looking to order everything I would need off amazon.
Just passed the Technician test myself and waiting on my license. I used a piece of 1 inch PVC pipe to stick in my mast pole for the 2 meter antenna to sit on. You could get by with RG-58U, RG-8U or RG-8X coax cable. I'm using 100 feet of RG-58U to go from the SO-239 connector to my radio which is a little Yaesu FT4VR HT I got from the local Ham club for passing the test.
Noob questions!
What is better, ¼ wave or ½ wave?
Can you turn a ½ wave into a ¼ wave?
One is not better than the other, only different. A 1/4 wave and 1/2 wave VHF antenna roughly have the same amount of gain. The benefit of a half wave is that it does not require a ground plane or radials, but it needs a matching system to bring the impedance to 50 ohms at the feed point. 1/4 wave antennas do not need matching as they are close to 50 ohms at the feed point, but require a ground plane or radials. The choice of one over the other depends on where it will be mounted or how it will be used. For example: 1/4 wave antennas are great for mounting on vehicles as the vehicle body acts as a ground plane. They are also easier to build if you want to put a simple antenna on the air. 1/2 wave antennas are often used where a suitable ground plane isn't available, like on watercraft or vehicles with non-metallic bodies.
Would like to get a copy of your plans in order to present it during an ARES class for new HAMS. It that possible?
Hello sir.. is copper wire coated mildsteel inside will work as well for the radiator??? Ty sir
Copper clad steel will work just fine. I've built this antenna out of copperweld and soft copper 12ga wire. They end result is the same
Hello, thanks for the video. I just bought my first mobile ill be using for a base station. (FTM-400XDR) i had it for a couple days and haven't even powered it up yet. Im still trying to get a power supply and some coax. so instead of dropping a couple 100 on an antenna this would be nice to get it up and running for the time being. what do you think? I am new. I passed my Tech exam and been still waiting for my call. its been 2 weeks and a day. still no call
This antenna will work well as a base station antenna for the FTM-400. Years ago I built a 1/4 dipole just like the one in the video and stuffed it in the false ceiling of my office. It will certainly get you on the air. Hopefully the call sign comes soon
Great vid! Question, I live in the Pacific Northwest and we get a lot of rain. I'm planning on making this antenna and was wondering about weatherproofing. Could I shoot a bunch of hot glue on the pl259 to keep water out? Will I get water inside the coax with a normal screw on connection? Thanks!
I think you can make a waterproof seal with hot glue. Otherwise silicon sealer would be my choice. As the cable connection, I'd wrap it up with high quality electrical tape so seal out the water.
@@KB9VBRAntennas thanks!
Hi Michael
I built the two meter quarter wave ground plane antenna ,I am measuring 2.7 SWR at 146 MHz .
What would be a good SWR for this antenna ?any suggestions to make my SWR better ,my copper wire is cut at 19.2 inches .thanks in advance .
At 19.2 inches, you should get a better reading. First off, may I ask what are you using as a SWR meter? Is it rated for VHF/UHF frequencies? A meter designed for HF/CB radio will give you a faulty reading above 30 Mhz and you will see an SWR of about 3:1 when you use it on VHF.
Before I build one of these and put it up on my roof, should I add a loading coil like the ones I see inline with the radiating element like on the mag mount that I bought (that seems to work OK)? Is there anything to 'gain'?
Since this is a quarter wave antenna‚ no loading coil is necessary.
Greetings from Sweden 🇸🇪
Great channel!
You just got yourself a new subscriber 🤖
Thank you!
Newbie here, just curious why not a half wave instead of quarter, is quarterwave better for vhf ?
A quarter wave is easier to work with. A half wave antenna has an advantage of not requring a ground plane, but the impedance is different at the feed point so you need a matching network to create 50 ohms of resistance. Quarter wave antennas have 50 ohms at the feed point but require a ground plane.