Thanks for that suggestion and good idea. I actually was able to test out a temporary arrangement at my qth with the dipole in an inverted-v with the peak at about 40 feet and the ends at 15 foot. That improved the received signal a bit but the noise was still bad. I agree that much of this noise is likely man made and generally it’s only on 40 meters. Every now and then there is a good night when the noise floor is only about 5, but most nights it’s 7-8. On DX transmit though, the vertical is much better than the dipole. Now my next thing, I’ll be relocating to another city so I get to start finding the best setup all over again, but that’s just part of the hobby. Thanks for your comment.

Thanks. What you just said confirms and lines up with the software modeling too. Thanks for your contribution to the channel! 73 .

@@acestudioscouk-Ace-G0ACE The hoop doesn’t connect electrically to the radials, it just holds them in their position. On the close proximity of the other antenna I don’t have any interference on 10 meters with it on the top of the pole. Now, 40 meters is another story. They are all over each other and I have to lay the one I’m not using flat on the ground. Even then the radials still try and interact with each other. I definitely need more room. I have 3 working antennas and trying to find a place for testing is becoming challenging. Thanks for watching and commenting.

@@yqtszhj Thanks for your clarifications, I really appreciate it. The fibreglass material you used for your hoop is not something we have in the UK, as far as I know. Interesting that your radials compete and yes we always need more space. best 73.

Thanks for watching.

@@k9tm yeah, the video doesn’t pick up the audio real well. The low mounted dipole reduces the noise significantly without reducing the received signal. It lowers the noise floor without attenuating the signal (improves the overall signal to noise ratio.) turning down the RF gain on the vertical reduced everything. The noise is reduced by about 3 s-units on a bad night while the signal is usually reduced by only about a half s-unit. I tried the loop-on-ground antenna and it cut the noise significantly but the signal was reduced a lot too. The dipole at 2 meters works better.

Surprisingly Not too bad. The SNR is improved greatly. It would have sounded a little better if the RF gain was turned down a little.

5 meters of elevation would be good. I find the driven elements of the higher frequencies are a little low to the ground if you’re in a developed area with a commander style antenna. If by chance you have guy-wires you can use them to get elevated radials to ground level or use them as radials if you add insulators (I’ve been toying around with that idea.) I’ve found the thing about running a cable down the mast is sometimes it starts to turn into an off center fed dipole then I have to deal with that, and I’m also trying to stay away from guyed mast, chokes, Baluns, ununs, and that sort of thing. I plan on trying something for 20 meters next and if I can get that to work like I want then I’ll try 40 meters. Thanks for watching and for sharing your ideas.

Thanks. There is more to come!

@@Snarky_Radio I bet it would work.

Yes it will work

Interesting, thanks!

I’ll put together something and post it maybe next week. It’s very simple and provides a great benefit.

Glad it was helpful!

@@billgoodson47 I’m using the Yeasu FT-710. Most of the newer Yeasu HF radios offer the display port I believe. That was the very reason I picked it up since my eyesight is showing my age.

@ I have a 991 and have the same vision issue. That is why I asked.

@@JayN4GO I like the way you think. I have thought the same thing.

@ I’ve spent many years building antennas. It’s a ton of fun. N4DJ don has always put out good videos and helped me out.

You have a good point. You can’t see from the video but the red and black leads are 14 awg, just not enabled copper. But if I changed it even to 10 awg that may take care of some of the insertion loss too. I just may try that. Thanks for your comment.

@@rolnas21 Yeah, I thought about that. I may do that if I ever rewire it, only I’ll use a shielded wire instead of full coax for the red leads. I have used that in a previous job and it works well. Fortunately insertion loss was not bad on the bands I normally work so I didn’t bother since I didn’t have any on hand. Thanks for watching and the suggestion.

@@rolnas21 Thanks for watching. It isolates any potential backfeed from the outside box from getting back into the PTT relay portion (think towards the radio) through the control feed. Maybe overkill but the part was there and it is cheap insurance. I’ve seen enough unexpected things happen over the years that it’s worthwhile.

Sounds like a good one. The combination of the receive antenna with PTT control works much better than I would have imagined.

Surprised me too. I think the greater loss with the small relays is due to either surface area of the contacts or smaller conductors for the signal. I had hoped to miniaturize the whole thing but I guess I’ll have to look at higher quality components if I go down that route. Thanks for watching.

It is possible. It is noise free though. That was handled on the repeater build.

Thanks for the tips. Been there, done those. My noise is things like my neighbors hvac unit too.

@@daveborchard2019 Good question. I can and have used the dipole for xmit but it works more like a NVIS antenna coming in about 2 s-level below the vertical. In short I can talk to Texas and Ohio 400-500 miles away but I can’t DX to Europe. My noise is likely at least partially caused by an antenna farm on top of a mountain about 2 Miles from my location, along with all the noise from my neighbors. Wish I owned that ridge for sure.

@@yqtszhj It's also an NVIS antenna on receive.

@@70looney That does help, and when used in conjunction with the low mounted dipole it’s better. Thanks for sharing the tip.

Putting attenuation on receive reduces both the noise and the signal and worsens your receiver's noise figure. It does absolutely nothing to improve the signal to noise ratio. Attenuators should only be used when strong signals are overloading your receiver.

@@stargazer7644 works for now i can work the station s1 s2 s3 with 3db att before i had s3 to s6 nosie floor heard nothing this is sdr has a very good rx 3 db att is nothing to it

@ Agree and thanks for commenting. The signal has to be greater than the noise to get any audible perceived benefit from any attenuation but is does nothing for signal to noise ratio as you have said. The beauty of the low mounted resonant dipole is it cuts the noise from S7 to S1 while the signal that is an S3 or S4 still comes through only now above the noise floor thereby improving the noise figure. Thanks for sharing.

@@yqtszhj Horizontal antennas can help with noise problems because most man-made noise sources are vertically polarized. Therefore horizontal antennas tend to be quieter. Having one so close to the ground will also greatly limit the antenna's sensitivity at low angles which is where nearby man-made noise usually comes from. Unfortunately that's also where long DX comes from so there are tradeoffs. The noise figure of a well designed radio is mostly set by the first amplifier and any attenuation placed before it. Antennas don't really change your receiver noise figure - they affect your receiver's gain. Noise figure represents noise added by your receiver's components to the incoming signal that degrades the SNR.

@@kmh752 Good suggestion. Actually in the next video I’ll show how I have it set up where when I press the PTT it automatically switches to the vertical transmit antenna and disconnects the dipole. Releasing the PTT then switches it back to the dipole. Also I can lock it on antenna A, antenna B, or use A for transmit and B for receive. It has 3 options.

Thanks for watching!

That would be pretty long for 40m

@@miker8379 Why? Standard AOR or Diamond t2fd are about 20 meters long that is equal to dipole setup which is used by topicstarter at the moment 2x10 m...advantage here is a wide frequency range and to receive only it`s quite effective with less noise.

Thanks for that suggestion. The dipole currently is disconnected completely from the feed line when transmitting also so disabling a preamp should be pretty easy. Good suggestion about putting it at the feed point also. Thanks!

I agree, those are great transmit antennas.

Thanks for sharing. The aluminum part whips something crazy when the wind picks up so I must have lucked up supporting it like I did.

Those are nice. Did you buy any of the add on modules for the RTR-2? Just wondering.

Ah, probably so. Stay tuned for the next video where I’m going to go over how I built the automatic antenna switch. In short I use the linear port on the radio (+13 volts, gnd, and PTT ground) to drive an optical relay bought off Amazon to switch the antenna.

Good question and it would be something that I would try simply out of curiosity. It may depend on local noise sources but I would think it would ground out signals you’d want to receive, on the other hand if it by chance resonates on some frequencies then you may benefit. That’s why we’re always tinkering around. Plus there are so many variables at any location that what works at one location may not be ideal for another. Important thing being new is to enjoy the hobby, try something new, and keep learning. Don’t let any negativity spouted by others stop you from enjoying and learning. 73!

Dipoles need distance from anything conductive, at least 1/4 wave but more is better. In rare circumstances you could use a chain link fence as a *reflector* and increase signal strength in a direction broadside from the fence. This would also reduce noise coming from the other side but shielded by the fence. You'd need some distance from the fence and depending on that distance you will have some pronounced lobes in the signal elevation. Dipoles do not use a counterpoise as such; each half of the dipole is counterpoise to the other half. Same with magnetic loop antennas. No counterpoise OR ground plane in that kind of antenna.

I agree and good points. My findings so far at my QTH is that for receiving local stations (few hundred miles) the dipole is slightly worse. For long multiple hop signals (across the Atlantic for example) it makes little difference because after bouncing off the ionosphere we don’t know what the polarization is. I lose about one S-level on receive from Europe but my noise drops 7 so my S/N is greatly improved. Some interesting transmit results are that for NVIS the Dipole still works pretty well but on test from here to Italy, when my vertical gets to them at an S7, the Dipole is an S2 or S3 which is deep in their noise floor, which is to be expected. I was actually surprised they could copy me at all but they have much cooler stuff than I do.

Excellent points on isolation. I need to try a mag-loop also, haven’t tried that yet.

@@traderlarry In my simple mind it works like this. The theory says that when a horizontal polarized antenna is placed close to the ground it responds more to the vertically polarized signals only, because the ground mutes the horizontal signals. In my location my noise appears to be horizontally polarized and my 35 foot tall vertical picks up that noise. The low mounted dipole does not pick it up. I would think that the correct receive would have to be chosen by location because every situation is different. Now all that said, I might have got the polarization completely backwards and if so someone will chime in. Hope this helps answer your question.

thanks for the question.and the detailed answer!

@@michaelpolimer2128 Thanks. I’ll be trying a LOG. I saw Callums videos about those and it was very interesting. I just haven’t made me a transformer yet but it’s on my list (list too long and time too short.j Thanks for sharing about your RX arrays.

Same recommendation. I built a LOG and it is a fantastic receive antenna especially 40 and 80 meters.

Excellent point about the RF Gain and Audio Gain. That makes a huge difference too. Thanks for sharing the 1 Meg resistor tip also.

I'm very new to HAM and I was advised to crank the RF gain all the way up first. I'm literally reading this at 05:30 in the morning, I just fired up my IC-705 to try AF first, then RF gain and worked fantastically! The only thing that I had to tweak was the DB "REF" on the waterfall as mine was previously set to a permanent+20 dB. Thanks so much EI6DP! 73 de GB, M7VOK

Hello Patrick - If you operate with the RF Gain fully advanced its akin to driving with your foot to the floor, *Everything* will be heard even a mouses fart. By reducing the RF Gain you are limiting what is being received, I should mention also to leave the pre-amp off unless you working a weak station. 73 de Ger

@EI6DP Thank you for the helpful contribution!

Yep, agree. To high an RF gain makes noise worse. So if you can't change antenna, then backing off RF and increasing audio is a good idea. Especially on SDRs that overload very easily. 73 Ed