Interesting stuff Brian. Gives hope to those with small gardens and short radials. 73 Peter.
@brianfields4479
5 ай бұрын
Thanks Peter for your kind words. Hearing from licensed op,s who are struggling to use mmnma before attempting to make a ant, is worrying to. It seems sometimes folk are losing the interest and excitement of the hobby, by getting everything ready made or have a 100 diagrams of something before having a go themselves. As I said to another radio op today, would ham radio suffer if you tube closed hi. Some seem to think youtube is part of the license these days hi. When you listen to live streams, you can hear people working dx, but not actually hearing the guy on his own radio, because the response is always delayed hi, in other words using KZitem as his rx hi. 73 mate.
@MidlifeRenaissanceMan
5 ай бұрын
I’m in a corner terrace / corner shop in the inner west of Sydney with a back yard that would just fit a 20m loop, with the domestic supply running along the street next to me My antenna is 33ish feet of self supporting telescopic drawn aluminium tube with a whip on top. 1.8m copper clad stake in the ground nearby. Match box is 3:13 turn 18:1 balun. It works on 40m and 20m. No tuner While I have practically no room for radials, save some short ones along the fence, I have been looking at the idea of a half wave with radials. As far as I have understood, it’s all in the length….keeping our minds out of the gutter….and as you approach that magic 0.64 wavelength your radiation pattern pushes out further….given the same ground conductivity. So…. Your same setup, but with the same short ground radials underneath the End Fed Half Wave, and a suitable match, because it’s not going to be 49:1 anymore, the half wave should out perform the quarter wave by a dog biscuit or two. Not much. I would expect a non grounded antenna to be an S point below a grounded antenna Now, what people often think is to use a quarter wave on a lower band as a half wave on a band that’s double. It is doable, but your match box switching has to handle a lot of voltage for a high Z end fed. Easier to go outside and swap it over as I do when I want to work 80, or 15.
@dxscotland5901
5 ай бұрын
Great work Brian! I much prefer the method of building and testing in the real world environment over model software! 73s Gm4zji Chris
@brianfields4479
5 ай бұрын
After many comments and questions about this video, I think showing a reply might help to clarify a few queries : Taking into consideration this was only a basic test, mainly to see is there was any difference between the two ants. Because I have just spent nearly three years experimenting with parasitic ants, my first thought was to interaction , not only between the two ants I was testing, but also my other vertical ants I have. therefore I first detuned all my other ants, and the two ants i was testing were about 25m apart, as i mentioned on the video i think. time between the two results were just under 5 minutes, so no real change in the greyline movement or propagation in that time. The half wave vertical belonged to a freind of mine, so he set it up, but i think the balun/unun was from dx engineering. working out the difference in signal strength, about 2-3 S points between ants, I do not really think , any anomaly in the unun or ant distance would effect the results anyway. I am not saying everyone should switch to a 1/4 vertical with radials, and this experiment could give different results in another location, and people have their own choices, but even in setting up the two ants , one with radials and one without, it took about the same time, and I didnt have to have a 10m pole, which on the day needed guying due to weather, but the 1/4 wave was fine just sat on a ground stake. This is only my take on the situation, but overhaul I know which ant i would rather use. cheers mate, 73 brian zl3xdj. Reply
@Linas_LY2H
4 ай бұрын
Very interesting experiment! Thanks for sharing! 73! Linas LY2H
@mikesradiorepair
5 ай бұрын
It's not a HF antenna but I have experience with a 70cm repeater antenna with and without it's radials. We were changing over a local repeater from a single antenna with duplexer to dual antennas (one for RX and one for TX) with no duplexer. The 21 Foot long StationMaster RX antenna at 180 feet was replaced with a new one and a new antenna added at 40 feet lower on the tower for TX. New runs of 7/8" hardline were run to both and everything was going great until we looked at the weather radar map towards the end of the day. There was a thunderstorm quickly approaching and we quickly got our climber down off the tower. We tried out our new system and well, it just flat out sucked. We stood around in the repeater shack talking about what could be wrong and then I looked in the climbers bucket and saw the 8 little (only a couple inches long) ground radials. We had forgotten to tell the climber that the radials needed to be installed on the base of the antennas. We went back to the mountain top repeater site the next day and the climber went back up and stuck the 4 ground radials on each antenna and the repeater worked great. At least in this case the repeater lost probably 2/3 of it's range without the radials installed. When the antenna has a tight 7 degree beam width the slightest change in the radiation angle makes a enormous difference.
@clm111
5 ай бұрын
Much appreciated, thanks for letting us in on your real life results!
@brianfields4479
5 ай бұрын
Real life doesn't confuse or mislead folk. 73.
@GD415711
5 ай бұрын
Great video Brian, thanks and I look forward to our next QSO, 73, Drew, G0CZE
@petemillis4666
5 ай бұрын
Brilliant video Brian. I'm going to take some additional wire with me next time I set up on the beach. I generally only use one counterpoise wire on the ground and have not got round to comparing with several wires on the ground. I've been too lazy!! Best wishes, M3KXZ
@brianfields4479
5 ай бұрын
Not so many radials required on the beach, I only use 4.
@MM0OPXFieldRadio
5 ай бұрын
Great experiment Brian, can I ask some more questions in the detail? Were both antennas set up in your garden at the same time? if so what was the separation distance? Could the halfwave act as a reflector? What was the time difference between the CQ calls? HB9VQQ does this but uses simultaneous WSPR transmitters so both antennas transmit/receive at the same time. Could you repeat by running 1/2 wave then 1/4 wave then back to 1/2 wave. Could you repeat the experiment with radials on the halfwave? This would rule out radials (in part) What's the build of the 49:1? not all are build equal and some are really poor in efficiency terms. Great work again 😀
@brianfields4479
5 ай бұрын
hi colin, appreciate your comments, and hope you are well. Taking into consideration this was only a basic test, mainly to see is there was any difference between the two ants. Because I have just spent nearly three years experimenting with parasitic ants, my first thought was to interaction , not only between the two ants I was testing, but also my other vertical ants I have. therefore I first detuned all my other ants, and the two ants i was testing were about 25m apart, as i mentioned on the video i think. time between the two results were just under 5 minutes, so no real change in the greyline movement or propagation in that time. The half wave vertical belonged to a freind of mine, so he set it up, but i think the balun/unun was from dx engineering. working out the difference in signal strength, about 2-3 S points between ants, I do not really think , any anomaly in the unun or ant distance would effect the results anyway. I am not saying everyone should switch to a 1/4 vertical with radials, and this experiment could give different results in another location, and people have their own choices, but even in setting up the two ants , one with radials and one without, it took about the same time, and I didnt have to have a 10m pole, which on the day needed guying due to weather, but the 1/4 wave was fine just sat on a ground stake. This is only my take on the situation, but overhaul I know which ant i would rather use. cheers mate, 73 brian zl3xdj.
@MM0OPXFieldRadio
5 ай бұрын
@@brianfields4479 Good on you Brian. Always best to do what's best in your personal situation. I'm still on the fence and due to the data HB9VQQ obtained. He did 2 different antenna comparisons simlaltainiously with WSPR RTX. A Hyendfed EFHW against a DX commander and my adjustiwave. On 20m the EFHW had way more spots beyond 3000 miles. You could see the band closing for the 2 1/4 waves but the EFHW went on for another 30 mins getting spots. its definitely horses for courses with each location different in my opinion. Please keep the videos coming. I'm now trying to get time to adjust all my Hexbeam elements for resonance but struggling to find the time. Cheers.
@trinitron11420
5 ай бұрын
Great Brian, I wonder how many radials would hit a sweet spot on a new antenna on the market; the Cushcraft HV-4E, I'm very limited with space, I noticed your contacts are mainly CW, keep up the good work Brian, drop me a note about this new antenna please, thank you, AF4R...73'S
@johnrees44..G4EIJ
5 ай бұрын
Thank you Brian, and we’ll done.. The RBN, I’m sure, is a readily accessible facility that far too few hams take advantage of..73..John..G4EIJ
@williamkizer3445
2 ай бұрын
W wonder how the half wave would have compared with radials
@mobiltec
5 ай бұрын
I also have a TS480. I've got the HS model. Love it.
@brianfields4479
5 ай бұрын
With the qrp to qro and filters it works all the dx I want, and great qrp contacts. 73 zl3xdj
@mobiltec
5 ай бұрын
@@brianfields4479 Same to you. K7ZFI
@andy2E0JIU
5 ай бұрын
Thanks Brian,great work and puts alot of myths to bed.73
@brianfields4479
5 ай бұрын
Lots of myths are created by subscriber Hungary youtubers. Just look how many spend hours on complicated ants, to only qso a few thousand miles down the road. 73.
@andy2E0JIU
5 ай бұрын
@brianfields4479 spot on!!! I've tried loads of experiments with wires,verticals etc BUT 9/10 my cobweb at 25ft beats my efhw AND my vertical and is so much quieter.love experimenting
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