Do you know why the SWR appears low? They put a 52 ohm resistor in parallel at the feed point. Two parallel resistors will always read lower than the lowest resistance.
I ordered the tram 1411, then watched this and your other on the tram 1410. Went and ordered the D130J now and trying to cancel the tram. I appreciate you showing the connector so I know what to order.
Do you know how they accomplish this? There is a 52 ohm resistor in parallel at the input. Two resistors in parallel will always be lower than the lowest resistance. You could accomplish the same readings but putting a resistor in parallel with the Tram. SWR is no indication of efficiency, angle or much of anything else. A dummy load will give you a nearly perfect set from DC, well into the microwave band, but it's definitely not a good radiator. The same is true with this antenna. The 52 ohm resistor fools your meter into seeing a good match while the actual SWR may be higher than Willie Nelson on April 20th.
Ive had one of these up for about 3yrs and its taken several batterings one of which broke my hf vertical FANTASTIC broadband performance and has taken 50w fm with my long overs without issue The swr on mines was also under 1:1.5 on the fm segment of 4m which was a pleasant surprise Anyone wanting a single antenna for ham use AND listening to the v/uhf air or marine band cant go wrong
Very informative. I own the Tram 1411 discone which has an 11 meter center whip and two lower tuning radials amongst the scanner radials (basically a unity gain 1/4 wave). Mine has 1.2 to 1.7 SWR across 11 meters. I have made countless contacts via Sporadic E with it using 12 watts on SSB from Louisiana to Idaho and points in between. I have yet to check SWR on other bands, but after seeing your review, I will be buying this Diamond and a four way switch coupling my dual band 2m/70cm, 220 and 6m mobile rigs along with my scanner in the shack. Thanks for video!
I was totally shocked at the difference between the Tram and the Diamond. Night and day. I haven't got it installed yet, but I'm planning to do the same thing.
I own this Diamond and a Tram 1411. I only use them to receive air band and 2m / 70cm, and transmit on 2m / 70cm. They show nearly identical in my tests and use. The diamond is built much better though. I can't speak for the 1410 since I don't own one, but something seems off about the one you have.
Right? Not like there is super complicated internals on it. The Diamond tested out great, I went back for a second and third pass on the Tram, it just sucks. I looked at it, I couldn't see anything overtly wrong with it, but obviously, something is outta whack.
I know this video is old but I just watched it. The PL connector on the Tram antenna ... could it be that it does not make a connection on the center pin ? There will still be a capacity between socket and connector and the antenna will be somewhat working but at a higher impedance. I think this "ringing behavior" looks like it could be the case. Also the construction of the antenna seems to be alright.
Smart, using the LMR-400 coax. N connectors should be the connector of choice for UHF and above. Hams are stuck on the PL-259 though. The noise you saw on the SWR sweep can be caused by strong RF signals received by the antenna and disturbing the measuring bridge inside the RigExpert. Tune a receiver to that frequency and see what's there. IIRC, RigExpert mentions it in their manual or website. Even a $12K communications analyzer will do the same thing if there is a powerful paging tower nearby. As to what's causing the Wavy Gravy SWR sweep, have no idea. Never seen it before.
Louis, I agree on PL-259, them things are everywhere. The Diamond was $75 more than the Tram, and as you saw, looks freaking great on the RE. As for strong RF, that's a great point. I do live out in the county, so generally, I'm the only strong RF around for miles. Of course, someone else could have been messing with GMRS or whatever, without checking in with me! ;) Wavy-gravy - spot on description!
I would like to see this same test on 6M, 10M and 11M. The Tram says TX on all of these freqs, while the Diamond says TX on 6M, but 10M/11M certainly is in its RX range.
Discone antennas are great all-purpose antennas. I've had a few of them. Only downside is that being an omnidirectional antenna it doesn't give you a lot of punch. SWR isn't the only measure of a good antenna; a dummy load gives an SWR of about 1:1. I love Diamond antennas, always good quality. The Tram is alarming.
Wow....Im so HAPPY i found your video. I was going to order the comet DS 150s until i saw this. Comet is good....but i havent seen a lower SWR. Thanks so much.
Full disclosure: I love sponsored ham products (that work), sadly, mine are sponsored the same as this one. We're doing it wrong. 🤣 I've had a Tram 1410 for about 9 years, I never did properly test it, but this would explain why getting out on 2m and 70cm was horrible. I switched to a X50a for those bands a few years ago. I'm looking for something better for my SDRPlay (rcv only) scanner. The D130 might be what I'm looking for. Thanks for the review. Cheers & 73.
That diamond antenna is great. I've got a drop amplifier hooked up, with 3 SDR dongles plugged in. It is working great up in the 850Mhz range (local PS stuff). Works great on 2m/440. It ain't a Yagi, but works well for the cost vs performance on it.
Outstanding video, I've been wanting to get my technician license forever. I could ask you about 100 questions regarding Ham and everything else. Thank you for your time.
@drmikeyb1 - Thanks for the kind words above! Come and join me on the TOADS server. Temporarily Offline, TheSmokinApe, Chuck, and myself, as well as a host of other friendly, knowledgeable (and opinionated) hams that love to share info! discord.gg/aKqhrvcFSY
@@FEPLabsRadio Ok discord I've never used before, I set up an account and everything is it like a live blog. When do you have your live podcast. Last question, how much do you charge for either a phone call or email regarding questions within the ham relm. What's really embarrassing is I bought a BF-F8HP for LISTENING purposes only to get an idea of the lingo. I downloaded chirp and for the life of me can't figure out how to program it. So many questions.
Interesting using set screws to keep legs in place ! Perhaps lesson learned ? I have seen some Discone antenna legs vibrate out, falling to the ground, after being subject to various wind speeds, over time ! Likely resulting from the builder not securing the double locking nuts properly ? But there is no escaping, if you want to fully take advantage of their extreme frequency range, you must use the best feed line you can afford ! As attenuation at those Frequencies is insane ! Likely where your anomalies you question are coming from ? Perhaps Standing Waves ? Maybe this one will hold up better ?
Well without a thorough examination, you may never know ? Could have been poor Coax, bad connection, location, etc. hard to say ? As Discone antennas are by design Unity gain antennas, and fed properly, are a good fit such as your multiband scanner application ! But because of their frequency gymnastics, and typically High frequency design, it is hard not to end up in negative numbers, when you're dealing with Unity gain to begin with, and unless you're feeding them with feed line the size of a Fire hose, the losses in feed line are horrendous , to say the least ! I have never been a Fan of the mods manufacturers made to appease those crying about their needs for some type of lower frequency capabilities, hence the vertical whips added over the years ! Which in my understanding, makes them no longer a Discone ! But Manufacturers will do anything to sell something, right or wrong ! Because of the above mentioned reasons, I have found most antennas supplied with scanners, do just as good a job at receiving, if not better ? I employed one many years ago, made for Radio Shack, or Tandy, I'm no longer sure who they were back then, maybe even, Allied Radio shack (?), specifically for their frequency flexibility, as back before many had ventured into UHF, it served as a quick and easy, " No Switch Box " option to switch from Two meters to 70 cm, in the blink of an eye ! And good SWR, to boot ! Really unique, back in the day ! And I believe because of their design, the input impedance is 50 ohms ! So they do have a nich place, but just difficult to rangle the losses ! From my experiences, anyway ! Good luck and most of all, have fun experimenting ! '73 !
As someone that's recently installed a tram discone for my sdrplay, your data reflects my experience, I can't pick up signals seemingly as well as my HT...
It was horrible! When I got the Diamond discone, I slapped it on the same coax run, and it tests out and works perfectly fine. There is something janky with the Tram antenna.
Thanks for this vid... Was considering Tram, Diamond and Comet discones. Found posts that emphasized Diamond of the others with anecdotal testament to everything you are showing with you scans! Definitely going to order the Diamond. Mt question is, what is an acceptable height to mount the antenna? Any what would be the performance difference mounted about 30+ feet on chimney vs sort-term / medium term mount on a post at say 12ft in height?
Mine is literally mounted on 2 10ft sections of chain link fence top rail, sitting on the ground. The bottom of the mast is sitting on the dirt, inside a concrete block, and I have the mast guyed to my shop building. With anything, height is might. 30ft on a chimney would beat the hell out of 12ft. Better reception of longer distance and weaker signals.
The "915MHZ" 902-928MHz is an ISM band. It doesn't require a license and is used for everything from LoRa/Meshtastic to smart electric meters. I'm curious how this antenna works on the 10 (28MHZ) and 11 (27MHz/CB) meter bands. Have you tested this antenna for these frequencies?
Glad the diamond did so well. Pretty much matches the swr scans I have with mine. Like I said on the other vid, I use mine often on repeaters, as well as simplex and 2m SSB. It does very well as a good Omni vhf/uhf antenna. 73 Jim, W3VAC
years ago I had a radio Shack Discone antenna that I used on 12 meters, 10 meters, 6 meters, and 2 meters al0ng with CB.. And it was great- It used the full length metal Jeep like antenna that I used sometimes on my Jeep.. and believe t or not, I did use it on 20 meters with a tuner, and 40 meters to work 20 states, but then I built a weird antenna based on a folded dipole but using old coax from the cable company for Forty and got a much better signal..lol
Yeah these things are super wide-banded. I think the power limit on the Diamond is like 200W, and if I remember right, it was not too bad out of whack on HF.
Silly question on the LMR400 I want to buy this antenna the diamond he previewed in the video but when I went to look at the LMR400 I didn't realize there were so many different ones. I want to run to either my SDS100 or SDS200 so which ends will I need. Thank you.
@@drmikeyb1 If you are buying LMR400 with ends, I'm thinking you'll want N connectors on both ends. After that you can adapt at the scanner from the N to what ever you have. I'm guessing that is your question? Make sure which connector your antenna has when you order. I'm thinking that this particular antenna has the SO239 connector option also besides the N.
Have you tried the Diamond D3000N Discone antenna... I believe it is a bigger antenna compared to the Diamond D130... The D3000N is also rated much higher at 25-3000 MHz rather than the 25-1300MHz for the D130.... I'm debating on which one to get... the D3000N or the D130...
I haven't - but I need to replace/upgrade my elderly discone, I will be getting a diamond for sure. I don't specifically have anything up above 1.2 (and barely 1.2), so if price is a factor, I'll probably go cheaper.
@@FEPLabsRadio from what I have been seeing the D130 is about $20-$30 cheaper.... in most cases... in other cases, it's almost the same price... Also, I was wrong about the size of the antenna. They are both the same size and weight.... the only thing is there really a big difference between 1300 and 3000 MHz ? From what I have been reading the Diamond D3000N is the first original antenna made by Diamond... Some testing needs to be done... 🙂 As of right now I'm running off a 500ft 12g sold core copper long-wire that is looped around the top of my 6ft dog-wood fence. The radio I'm using is the very popular RTL SDR USB dongle with SDRsharp... I love that little radio....
Right, honestly didn't even think about that, as I'm not using that antenna in those bands. VHF and up is where that guy gets used. Might be itneresting to go back and check that out.
Thinking about getting one of these or something similar to use with me RSPdx SDR receiver. I really wish I could get something resembling reception on HF/shortwave with an omni vertical. I'd love to put up a longwire, but it just isn't practical where I live.
Go for it! I use this guy out in my shop, usually with 2 sdr dongles connected to a drop amplifier, so I can monitor local sheriff and fire on the county P25 system. It also fills in as an ok test antenna, since it is so wide-banded.
yes that cost you. I got one for fifteen dollars at a flea market. it cost me ten dollar for the rod to get out on two meters. it worked great on two meters. I let it up north for my ex mate. being nice.. even left he a nice two meters radio..
Jim -Hollywood is spot on. I love the Diamond that I have. I use it for all of my RSPdx activity and love the S/N on this antenna even down in the HF bands. A very solid antenna. 73 - KF6IF
@@FEPLabsRadio The antenna covers 7 MHz to 30 MHz or 50 MHz without any traps or adjustments, and the high current point is at the top of the structure.
I'm wanting to buy this antenna with the LMR400. When I text DX Engineering they asked if I need the lightning protection, I'll admit I didn't think about this. What do you recommend for this and do amps help that much on bring in a weak signal. Thank you
I'd recommend lightning protection. Those things are not super expensive, and decent enough insurance. I don't have a specific recommendation, I use the MFJ ones. A lightning arrestor is a pretty simple thing, and they all work well enough, unfortunately, you're never sure of that until the moment comes. I will say for years and years, I never put any on my scanner antenna, and it was fine. As for amplifiers, there are some amplifiers that will boost an incoming signal, but keep in mind, it will also boost the incoming noise. An amp is not going to make the signal better, just stronger (along with the noise). It may help in your specific case, but I couldn't tell you for sure one way or the other. If you're in a metro area, you really aren't going to hear any more than you would without one, IMO.
For weak signals, I would recommend a bandpass filter for what frequency range you are looking at. Mini Circuits - look at their RF Filter page. This will give you a good idea of where to start, then what to look for. For example, when picking up weak satellite signals, this is a requirement if you do not want the signal down in the noise of everything else going on. Remember to connect the filter between your tranceiver, and antenna tuner. Connecting between the antenna tuner and antenna makes things less than ideal, and increases SWR. Adding an amplifier should be after the bandpass filter obviously, between it and your tranceiver. Good luck!
Yes they are pretty much the same as the TRAM antenna. Amazon or ML&S or such would have the size dimensions - I'd say at the bottom cone area, it's pretty close to a meter in diameter.
I do have only 50ft run of cable on the Diamond now, just to eliminate that variable. I did re-mount the Tram on a tripod mast, and re-tested with about a 15ft section of RG-8X, and still got the hot garbage. I dunno what they did, but they broke it good. If I'd kept the packaging, I'd have sent it back.
Thanks Jim. That Tram is toast.😆 I'll be getting a Sirio SD 1300 U/N next week. It looks similar to the Diamond as well as bandwidth. Do you need to ground the mast?
I don't think it would hurt at all. My Diamond is on chain link fence top rail mast (2 sections), sitting directly on the ground (guy-ed off). Should work fine, either way.
Discone is a ground plane antenna. They do not need ground connection to function but it is a good idea for other reasons like close by lightning induction.
I have a bearcat 2500 xl. Will that COAX plug into my scanner? You say it's a PL259. I'm assuming that is the silver connecter that turns to lock in. Thank you so much. This looks like a great antenna for my scanner.
If I remember - the antenna is either a female N-type, or SO-239. Most scanners are BNC, so my recommendation is get good coax, and a bnc adapter to whatever , put that on the scanner side.
Nice video. A question for installers out there as this is a place who has experience. I have a discone antenna which is being installed apart from metering the cable end to end for continuity inner and outa. Once connected via N type aerial end and bare on the other before going up on the wall if I meter with a multimeter the inner core should it beep out on any part of the antenna and same with the outa cable? I take it it's not a loop in anyway? Should it beep on inner core to the whole antenna? Just thinking test wise before it goes up as have to pay to take it down again if it's wrong.
Hey Adam, I don't usually have help, so my raising of the mast is probably an OSHA violation! I used two chain-link fence top rails. I had the mast leaning against a saw horse, mounted the antenna to that. Then I just raised it up vertical, VERY close to where it was going to be mounted against the outside wall of my shop. I already had the bracket mounted and ready. I placed the bottom of the antenna in a concrete block to keep it steady and just leaned it into the shop and then fastened the bracket, and set some guy ropes.
Not really, as far as I understand it. It can have a *slight* effect on it, but it's basically non-existent. If the coax and antenna are matched at 50 ohms, then the effect is negligible. When you do see a difference in SWR with different cables, that can indicate that the antenna system needs a counterpoise and/or choke, so that you are not radiating on your cable. Again, generally negligible.
The impedance match looks impressive. Suspicious impressive. Discones are pretty wideband, but not with such a low vswr. Looks like a bunch of lossy coax. With such low transmit power ratings, it begs the question if they're using resistive loading (waste power in heat) If you repeat the test with a short line, we may see the true character. If it's still fantastic, put power to it to see where the resistor is heating. Historically, the problem with discones is not vswr bandwidth, it's the angle of radiation - above the low end of its frequency range, the angle rises above the horizon, so peak "gain" is not where you want it unless you're listening to high altitude aircraft...
I was going to make a similar comment. SWR means very little in transmit efficiency and radiation patterns. I wouldn't be surprised if this discone had a parallel resistor to keep the SWR appearing low.
I have no idea. It's on a temp pole outside, I haven't been motivated to tear it down and find out why it's so bad. I had no idea you could mess up a discone as much as that one is. I looked at it, no obvious problems at all.
Right? It baffled me totally. There's not much to a discone, it's certainly not complicated other than the elements. I suspect something is shorted inside maybe. I haven't troubleshot it any more, it's just sitting there on a test mast, head hung in shame. I probably need to either fix it or throw it away.
Good follow up video. At least now we see that discones antennas do work, just the Tram doesn't. Just showing the Tram in the early video you might come to the conclusion that discones aren't great antennas, but this video shows they are and the Tram is garbage.
Yeah, it really blew me away Ron. Before I shot the tram video, I had already run sweeps on The Elder, and knew it wasn't junk, just old. So, two out of three look good, and the Tram - well, it's Krap.
Please ship me that horrible Tram Antenna. It is better than what I currently have, which is nothing. I will work on it and see if I can fix those issues
I’m not sure about any ham allocations in the 902-928 mHz band. It is, however, the (unlicensed) ISM (Industrial, Scientific, and Medical) band where new and exotic modulations exist, like _LoRa_ (chirp spread spectrum) and _MeshTastic,_ a sub-mode of LoRa. 73 de AF6AS
I really got it for my scanner, and it works great for that. They're advertised as being able to transmit, and my results were based really on what SWR showed up with the rigexpert. Obvi, there are a lot better antennas for HF/VHF/UHF than a discone. it is a compromise.
Its only a bit worse than a 1/4 wave ground plane so not bad at all. A thing to know allthough is that it isnt strictly horisontal or vertical polarized it is both and everything in between depending on frequency.
I have this Diamond D3000N antenna, it does transmit but it does not hear that well. I’m curious if you put that Trim antenna on that new coax where you have the Diamond mounted if it does any better on the SWR scans.
I never really do anything around here with 6M. I mostly bought this as a scanner antenna/satellite (maybe?). I'll have to put the RigExpert on it and see how 6m tests out.
Do you know why the SWR appears low?
They put a 52 ohm resistor in parallel at the feed point. Two parallel resistors will always read lower than the lowest resistance.
I have a tram 1411 was using it in the 27Mhz cb band 1.8 swr ... love it, like that the coax comes down through the center pole....
I ordered the tram 1411, then watched this and your other on the tram 1410. Went and ordered the D130J now and trying to cancel the tram. I appreciate you showing the connector so I know what to order.
Glad it helped, thanks for watching!
Do you know how they accomplish this?
There is a 52 ohm resistor in parallel at the input.
Two resistors in parallel will always be lower than the lowest resistance. You could accomplish the same readings but putting a resistor in parallel with the Tram.
SWR is no indication of efficiency, angle or much of anything else.
A dummy load will give you a nearly perfect set from DC, well into the microwave band, but it's definitely not a good radiator.
The same is true with this antenna. The 52 ohm resistor fools your meter into seeing a good match while the actual SWR may be higher than Willie Nelson on April 20th.
Ive had one of these up for about 3yrs and its taken several batterings one of which broke my hf vertical
FANTASTIC broadband performance and has taken 50w fm with my long overs without issue
The swr on mines was also under 1:1.5 on the fm segment of 4m which was a pleasant surprise
Anyone wanting a single antenna for ham use AND listening to the v/uhf air or marine band cant go wrong
Exactly. I use mine as an sdr scanner antenna (thru a multidrop), also use it for 2m/440. I've been very pleased with this antenna.
Very informative. I own the Tram 1411 discone which has an 11 meter center whip and two lower tuning radials amongst the scanner radials (basically a unity gain 1/4 wave). Mine has 1.2 to 1.7 SWR across 11 meters. I have made countless contacts via Sporadic E with it using 12 watts on SSB from Louisiana to Idaho and points in between. I have yet to check SWR on other bands, but after seeing your review, I will be buying this Diamond and a four way switch coupling my dual band 2m/70cm, 220 and 6m mobile rigs along with my scanner in the shack. Thanks for video!
I was totally shocked at the difference between the Tram and the Diamond. Night and day. I haven't got it installed yet, but I'm planning to do the same thing.
You normally get the 'heart beat' looking swr from the reflected RF on your line. Should see that disappear if you use a LMR 400 cable.
I own this Diamond and a Tram 1411. I only use them to receive air band and 2m / 70cm, and transmit on 2m / 70cm. They show nearly identical in my tests and use. The diamond is built much better though. I can't speak for the 1410 since I don't own one, but something seems off about the one you have.
Right? Not like there is super complicated internals on it. The Diamond tested out great, I went back for a second and third pass on the Tram, it just sucks. I looked at it, I couldn't see anything overtly wrong with it, but obviously, something is outta whack.
I know this video is old but I just watched it. The PL connector on the Tram antenna ... could it be that it does not make a connection on the center pin ?
There will still be a capacity between socket and connector and the antenna will be somewhat working but at a higher impedance. I think this "ringing behavior" looks like it could be the case. Also the construction of the antenna seems to be alright.
Smart, using the LMR-400 coax. N connectors should be the connector of choice for UHF and above. Hams are stuck on the PL-259 though.
The noise you saw on the SWR sweep can be caused by strong RF signals received by the antenna and disturbing the measuring bridge inside the RigExpert. Tune a receiver to that frequency and see what's there. IIRC, RigExpert mentions it in their manual or website. Even a $12K communications analyzer will do the same thing if there is a powerful paging tower nearby.
As to what's causing the Wavy Gravy SWR sweep, have no idea. Never seen it before.
Louis, I agree on PL-259, them things are everywhere. The Diamond was $75 more than the Tram, and as you saw, looks freaking great on the RE. As for strong RF, that's a great point. I do live out in the county, so generally, I'm the only strong RF around for miles. Of course, someone else could have been messing with GMRS or whatever, without checking in with me! ;)
Wavy-gravy - spot on description!
I would like to see this same test on 6M, 10M and 11M. The Tram says TX on all of these freqs, while the Diamond says TX on 6M, but 10M/11M certainly is in its RX range.
Darrell, that is not a bad idea for a follow-up! I'll look into it
Discone antennas are great all-purpose antennas. I've had a few of them. Only downside is that being an omnidirectional antenna it doesn't give you a lot of punch. SWR isn't the only measure of a good antenna; a dummy load gives an SWR of about 1:1. I love Diamond antennas, always good quality. The Tram is alarming.
EXCELLENT antenna comparison video! It was a huge help to me in considering which discone antenna to purchase...thank you!
Nice work. This discone looks a wee bit better!
Wow....Im so HAPPY i found your video. I was going to order the comet DS 150s until i saw this. Comet is good....but i havent seen a lower SWR. Thanks so much.
It was night and day difference between the two - I was really surprised.
Full disclosure: I love sponsored ham products (that work), sadly, mine are sponsored the same as this one. We're doing it wrong. 🤣 I've had a Tram 1410 for about 9 years, I never did properly test it, but this would explain why getting out on 2m and 70cm was horrible. I switched to a X50a for those bands a few years ago. I'm looking for something better for my SDRPlay (rcv only) scanner. The D130 might be what I'm looking for. Thanks for the review. Cheers & 73.
That diamond antenna is great. I've got a drop amplifier hooked up, with 3 SDR dongles plugged in. It is working great up in the 850Mhz range (local PS stuff). Works great on 2m/440. It ain't a Yagi, but works well for the cost vs performance on it.
Damn it Jim now I need another antenna! Great video!
Dude, as you can see, this sucker is great for RX and TX. I've been thrilled with it so far. Got it permanently mounted today. I highly recommend!
Outstanding video, I've been wanting to get my technician license forever. I could ask you about 100 questions regarding Ham and everything else. Thank you for your time.
@drmikeyb1 - Thanks for the kind words above! Come and join me on the TOADS server. Temporarily Offline, TheSmokinApe, Chuck, and myself, as well as a host of other friendly, knowledgeable (and opinionated) hams that love to share info! discord.gg/aKqhrvcFSY
@@FEPLabsRadio Ok discord I've never used before, I set up an account and everything is it like a live blog. When do you have your live podcast. Last question, how much do you charge for either a phone call or email regarding questions within the ham relm. What's really embarrassing is I bought a BF-F8HP for LISTENING purposes only to get an idea of the lingo. I downloaded chirp and for the life of me can't figure out how to program it. So many questions.
Interesting using set screws to keep legs in place !
Perhaps lesson learned ?
I have seen some Discone antenna legs vibrate out, falling to the ground, after being subject to various wind speeds, over time !
Likely resulting from the builder not securing the double locking nuts properly ?
But there is no escaping, if you want to fully take advantage of their extreme frequency range, you must use the best feed line you can afford !
As attenuation at those Frequencies is insane !
Likely where your anomalies you question are coming from ?
Perhaps Standing Waves ?
Maybe this one will hold up better ?
Same piece of feed line (RG-213 - I think), only about 20 feet long. Same mast, same hookup. It's strange, the difference between the two antennas
Well without a thorough examination, you may never know ?
Could have been poor Coax, bad connection, location, etc. hard to say ?
As Discone antennas are by design Unity gain antennas, and fed properly, are a good fit such as your multiband scanner application !
But because of their frequency gymnastics, and typically High frequency design, it is hard not to end up in negative numbers, when you're dealing with Unity gain to begin with, and unless you're feeding them with feed line the size of a Fire hose, the losses in feed line are horrendous , to say the least !
I have never been a Fan of the mods manufacturers made to appease those crying about their needs for some type of lower frequency capabilities, hence the vertical whips added over the years !
Which in my understanding, makes them no longer a Discone !
But Manufacturers will do anything to sell something, right or wrong !
Because of the above mentioned reasons, I have found most antennas supplied with scanners, do just as good a job at receiving, if not better ?
I employed one many years ago, made for Radio Shack, or Tandy, I'm no longer sure who they were back then, maybe even, Allied Radio shack (?), specifically for their frequency flexibility, as back before many had ventured into UHF, it served as a quick and easy, " No Switch Box " option to switch from Two meters to 70 cm, in the blink of an eye !
And good SWR, to boot !
Really unique, back in the day !
And I believe because of their design, the input impedance is 50 ohms !
So they do have a nich place, but just difficult to rangle the losses !
From my experiences, anyway !
Good luck and most of all, have fun experimenting !
'73 !
Thanks for the great informative video. Can you also do a wide-band sweep of SWR including the civil and mil airbands?
Great suggestion! - If I can remember to do that, it would be a neat follow up!
As someone that's recently installed a tram discone for my sdrplay, your data reflects my experience, I can't pick up signals seemingly as well as my HT...
It was horrible! When I got the Diamond discone, I slapped it on the same coax run, and it tests out and works perfectly fine. There is something janky with the Tram antenna.
@@FEPLabsRadio yo, thanks for this reply. If you have a model you'd recommend I'd love a starting point
@@theg0z0n The one in this video is what I have up now. The Diamond D130 - amzn.to/3ziE61T
@@FEPLabsRadio as soon as I asked I knew the answer, but couldn't figure out how to delete my comment, thank you!!
Thanks for this vid... Was considering Tram, Diamond and Comet discones. Found posts that emphasized Diamond of the others with anecdotal testament to everything you are showing with you scans! Definitely going to order the Diamond. Mt question is, what is an acceptable height to mount the antenna? Any what would be the performance difference mounted about 30+ feet on chimney vs sort-term / medium term mount on a post at say 12ft in height?
Mine is literally mounted on 2 10ft sections of chain link fence top rail, sitting on the ground. The bottom of the mast is sitting on the dirt, inside a concrete block, and I have the mast guyed to my shop building. With anything, height is might. 30ft on a chimney would beat the hell out of 12ft. Better reception of longer distance and weaker signals.
The "915MHZ" 902-928MHz is an ISM band. It doesn't require a license and is used for everything from LoRa/Meshtastic to smart electric meters.
I'm curious how this antenna works on the 10 (28MHZ) and 11 (27MHz/CB) meter bands. Have you tested this antenna for these frequencies?
It's passable on 11m, haven't tried it on 10.
just what I was looking for, thanks. So curious how it is on 10m and 6m since its in the limits
Glad the diamond did so well. Pretty much matches the swr scans I have with mine. Like I said on the other vid, I use mine often on repeaters, as well as simplex and 2m SSB. It does very well as a good Omni vhf/uhf antenna. 73 Jim, W3VAC
Yeah, I put this on the shop (and secured the mast...) I'm going to use it for a GP scanner antenna/2m/440 PRN. It's amazing the difference.
years ago I had a radio Shack Discone antenna that I used on 12 meters, 10 meters, 6 meters, and 2 meters al0ng with CB.. And it was great- It used the full length metal Jeep like antenna that I used sometimes on my Jeep.. and believe t or not, I did use it on 20 meters with a tuner, and 40 meters to work 20 states, but then I built a weird antenna based on a folded dipole but using old coax from the cable company for Forty and got a much better signal..lol
Yeah these things are super wide-banded. I think the power limit on the Diamond is like 200W, and if I remember right, it was not too bad out of whack on HF.
I’m still laughing about the Tram
Silly question on the LMR400 I want to buy this antenna the diamond he previewed in the video but when I went to look at the LMR400 I didn't realize there were so many different ones. I want to run to either my SDS100 or SDS200 so which ends will I need. Thank you.
@@drmikeyb1 If you are buying LMR400 with ends, I'm thinking you'll want N connectors on both ends. After that you can adapt at the scanner from the N to what ever you have. I'm guessing that is your question? Make sure which connector your antenna has when you order. I'm thinking that this particular antenna has the SO239 connector option also besides the N.
Have you tried the Diamond D3000N Discone antenna... I believe it is a bigger antenna compared to the Diamond D130... The D3000N is also rated much higher at 25-3000 MHz rather than the 25-1300MHz for the D130.... I'm debating on which one to get... the D3000N or the D130...
I haven't - but I need to replace/upgrade my elderly discone, I will be getting a diamond for sure. I don't specifically have anything up above 1.2 (and barely 1.2), so if price is a factor, I'll probably go cheaper.
@@FEPLabsRadio from what I have been seeing the D130 is about $20-$30 cheaper.... in most cases... in other cases, it's almost the same price... Also, I was wrong about the size of the antenna. They are both the same size and weight.... the only thing is there really a big difference between 1300 and 3000 MHz ? From what I have been reading the Diamond D3000N is the first original antenna made by Diamond... Some testing needs to be done... 🙂 As of right now I'm running off a 500ft 12g sold core copper long-wire that is looped around the top of my 6ft dog-wood fence. The radio I'm using is the very popular RTL SDR USB dongle with SDRsharp... I love that little radio....
You could have shown the SWR for lower bands as 28 MHZ and 50 Mhz since ads says is good tunable for transmitting on 50 MHZ
Right, honestly didn't even think about that, as I'm not using that antenna in those bands. VHF and up is where that guy gets used. Might be itneresting to go back and check that out.
Informative video, ta!
Thinking about getting one of these or something similar to use with me RSPdx SDR receiver. I really wish I could get something resembling reception on HF/shortwave with an omni vertical. I'd love to put up a longwire, but it just isn't practical where I live.
Go for it! I use this guy out in my shop, usually with 2 sdr dongles connected to a drop amplifier, so I can monitor local sheriff and fire on the county P25 system. It also fills in as an ok test antenna, since it is so wide-banded.
yes that cost you. I got one for fifteen dollars at a flea market. it cost me ten dollar for the rod to get out on two meters. it worked great on two meters. I let it up north for my ex mate. being nice.. even left he a nice two meters radio..
Jim -Hollywood is spot on. I love the Diamond that I have. I use it for all of my RSPdx activity and love the S/N on this antenna even down in the HF bands. A very solid antenna. 73 - KF6IF
I hope to install an HF 40-10 or 6 meter discone this spring.
I would guess the only difference would be element length? Seems like an interesting idea.
@@FEPLabsRadio The antenna covers 7 MHz to 30 MHz or 50 MHz without any traps or adjustments, and the high current point is at the top of the structure.
I'm wanting to buy this antenna with the LMR400. When I text DX Engineering they asked if I need the lightning protection, I'll admit I didn't think about this. What do you recommend for this and do amps help that much on bring in a weak signal. Thank you
I'd recommend lightning protection. Those things are not super expensive, and decent enough insurance. I don't have a specific recommendation, I use the MFJ ones. A lightning arrestor is a pretty simple thing, and they all work well enough, unfortunately, you're never sure of that until the moment comes. I will say for years and years, I never put any on my scanner antenna, and it was fine.
As for amplifiers, there are some amplifiers that will boost an incoming signal, but keep in mind, it will also boost the incoming noise. An amp is not going to make the signal better, just stronger (along with the noise). It may help in your specific case, but I couldn't tell you for sure one way or the other. If you're in a metro area, you really aren't going to hear any more than you would without one, IMO.
For weak signals, I would recommend a bandpass filter for what frequency range you are looking at. Mini Circuits - look at their RF Filter page. This will give you a good idea of where to start, then what to look for. For example, when picking up weak satellite signals, this is a requirement if you do not want the signal down in the noise of everything else going on. Remember to connect the filter between your tranceiver, and antenna tuner. Connecting between the antenna tuner and antenna makes things less than ideal, and increases SWR. Adding an amplifier should be after the bandpass filter obviously, between it and your tranceiver. Good luck!
Very interesting and useful thank-you. Please can you say if the physical dimensions, the element lengths were similar? Thanks.
Yes they are pretty much the same as the TRAM antenna. Amazon or ML&S or such would have the size dimensions - I'd say at the bottom cone area, it's pretty close to a meter in diameter.
@@FEPLabsRadio Thanks very much for the information!
Hello, good video. Did you try 50 and 70 MHz these allocations of 4 and 6 meters are used here in the UK. Thank you 73 de John G4YDM
No, sure didn't.
Great follow up. The oscillation could be capacitance related. I am just throw out an idea.
I do have only 50ft run of cable on the Diamond now, just to eliminate that variable. I did re-mount the Tram on a tripod mast, and re-tested with about a 15ft section of RG-8X, and still got the hot garbage. I dunno what they did, but they broke it good. If I'd kept the packaging, I'd have sent it back.
@@FEPLabsRadio Be interesting to sweep your coax run with a known good 50 Ohm dummy load on the far end too ...
Thanks Jim. That Tram is toast.😆
I'll be getting a Sirio SD 1300 U/N next week. It looks similar to the Diamond as well as bandwidth.
Do you need to ground the mast?
I don't think it would hurt at all. My Diamond is on chain link fence top rail mast (2 sections), sitting directly on the ground (guy-ed off). Should work fine, either way.
@@FEPLabsRadio thanks Jim.👍🍻
Discone is a ground plane antenna. They do not need ground connection to function but it is a good idea for other reasons like close by lightning induction.
I have a bearcat 2500 xl. Will that COAX plug into my scanner? You say it's a PL259. I'm assuming that is the silver connecter that turns to lock in. Thank you so much. This looks like a great antenna for my scanner.
If I remember - the antenna is either a female N-type, or SO-239. Most scanners are BNC, so my recommendation is get good coax, and a bnc adapter to whatever , put that on the scanner side.
Nice video. A question for installers out there as this is a place who has experience. I have a discone antenna which is being installed apart from metering the cable end to end for continuity inner and outa. Once connected via N type aerial end and bare on the other before going up on the wall if I meter with a multimeter the inner core should it beep out on any part of the antenna and same with the outa cable? I take it it's not a loop in anyway? Should it beep on inner core to the whole antenna? Just thinking test wise before it goes up as have to pay to take it down again if it's wrong.
The inner core connects to the "disc", and the lower "cone" is generally connected to the shield. They are not connected to each other.
I'd be interested in your mast setup? What do you use and your raising techniques.
Hey Adam, I don't usually have help, so my raising of the mast is probably an OSHA violation! I used two chain-link fence top rails. I had the mast leaning against a saw horse, mounted the antenna to that. Then I just raised it up vertical, VERY close to where it was going to be mounted against the outside wall of my shop. I already had the bracket mounted and ready. I placed the bottom of the antenna in a concrete block to keep it steady and just leaned it into the shop and then fastened the bracket, and set some guy ropes.
Just curious would the LMR400 be a big part of the great SWRs.
Not really, as far as I understand it. It can have a *slight* effect on it, but it's basically non-existent. If the coax and antenna are matched at 50 ohms, then the effect is negligible. When you do see a difference in SWR with different cables, that can indicate that the antenna system needs a counterpoise and/or choke, so that you are not radiating on your cable. Again, generally negligible.
What do you do for grounding and lighting protection for the D130?
Nothing special. I have a ground on my gear to the rod outside, that's it.
Does the diamond 3000 have any downside compared to the 130?
I could not tell you - I don't have a 3000. I would guess maybe more power or wider bandwidth.
@FEPLabsRadio Only difference in specs is it goes up to 3GHz vs 1.3. Dimensions are almost identical. Must be some tradeoff
have a home patrol 2, would this Diamond D130J DIscone Antenna: work with it, what do you think? thanks, AB8KC
Yes it will! I use it with multiple SDR dongles, as well as my SDS-100 Uniden scanner.
The impedance match looks impressive. Suspicious impressive. Discones are pretty wideband, but not with such a low vswr. Looks like a bunch of lossy coax. With such low transmit power ratings, it begs the question if they're using resistive loading (waste power in heat) If you repeat the test with a short line, we may see the true character. If it's still fantastic, put power to it to see where the resistor is heating.
Historically, the problem with discones is not vswr bandwidth, it's the angle of radiation - above the low end of its frequency range, the angle rises above the horizon, so peak "gain" is not where you want it unless you're listening to high altitude aircraft...
I was going to make a similar comment. SWR means very little in transmit efficiency and radiation patterns. I wouldn't be surprised if this discone had a parallel resistor to keep the SWR appearing low.
so what is the deciding factor here? materials, geometry? I dont get it
I have no idea. It's on a temp pole outside, I haven't been motivated to tear it down and find out why it's so bad. I had no idea you could mess up a discone as much as that one is. I looked at it, no obvious problems at all.
What is your coax length?
About 25 ft max.
Surely something was wrong with the Tram antenna. It doesn't seem reasonable that it would be like that by design.
Right? It baffled me totally. There's not much to a discone, it's certainly not complicated other than the elements. I suspect something is shorted inside maybe. I haven't troubleshot it any more, it's just sitting there on a test mast, head hung in shame. I probably need to either fix it or throw it away.
Good follow up video. At least now we see that discones antennas do work, just the Tram doesn't. Just showing the Tram in the early video you might come to the conclusion that discones aren't great antennas, but this video shows they are and the Tram is garbage.
Yeah, it really blew me away Ron. Before I shot the tram video, I had already run sweeps on The Elder, and knew it wasn't junk, just old. So, two out of three look good, and the Tram - well, it's Krap.
Please ship me that horrible Tram Antenna. It is better than what I currently have, which is nothing. I will work on it and see if I can fix those issues
Should have bought the Tram 1411 instead of the 1410.
Maybe I just got a clinker, but I don't know how complicated it is to screw up a discone. I was really amazed at how poorly that tram performs.
very interesting video
Glad you liked it! Thanks for watching!
I’m not sure about any ham allocations in the 902-928 mHz band. It is, however, the (unlicensed) ISM (Industrial, Scientific, and Medical) band where new and exotic modulations exist, like _LoRa_ (chirp spread spectrum) and _MeshTastic,_ a sub-mode of LoRa.
73 de AF6AS
@@ChaplainDaveSparks ham license allows one to run higher power but no encryption
Was looking for something new on Discones , thanks for the info .
A discone antenna is a wide band radiating dummy load.
I really got it for my scanner, and it works great for that. They're advertised as being able to transmit, and my results were based really on what SWR showed up with the rigexpert. Obvi, there are a lot better antennas for HF/VHF/UHF than a discone. it is a compromise.
Its only a bit worse than a 1/4 wave ground plane so not bad at all. A thing to know allthough is that it isnt strictly horisontal or vertical polarized it is both and everything in between depending on frequency.
Anyone who asks why the tested SWR of an antenna used for receive is important, needs to ask fewer questions that sound like statements.
what about 6m?
I didn't have a rig to test 6m with, and it's just not something I get a lot of around here. It should work ok, it's a very wide banded antenna
25 mhz to 2.5 ghz
I have this Diamond D3000N antenna, it does transmit but it does not hear that well. I’m curious if you put that Trim antenna on that new coax where you have the Diamond mounted if it does any better on the SWR scans.
I did that, I thought I mentioned in the video, but yes. Same mount, same coax, vastly different results.
Have you ever checked the MURS and GMRS bands on this? 151.82,151.88, 462.55-462.725, 467.550-467.725? Thanks
They're VHF and UHF on a wide-banded antenna. It'll work just fine
I spray painted mine brown and black. Cant even see it at nite. ✌️
ha! I did that with my copper jpole antennas. actually white trash camo painted.
6 meters please jim KB1PFL
I never really do anything around here with 6M. I mostly bought this as a scanner antenna/satellite (maybe?). I'll have to put the RigExpert on it and see how 6m tests out.
Do a full scan on all of them to their datasheet.