Shortwave radio antenna and ground demonstration 

I think the water conductivity is already pretty good. And yes my other half is a watercolourist - not me!

Nash102030 ... not sure the ground he has is good. I am on heavy soil with a clay substrata 36 inches down. I have a serious 72 inch cooper rod with only a couple of inches left above ground level and a heavy duty clamp. The difference was a s5 noise reduction .

@@robertl.fallin7062 Well dude prolly got tired.. Give'm a break. ;)

How do discones compare to loops? For reception only, they seem to cover larger bandwidth and they also are cheaper

@@02vLxcZF Active mag loops are superb for HF and (depending on the design) below - see ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-aky9sVS0rTU.html Discones can work well above 10MHz (depending on the design) and are excellent wideband non-directional antennas for VHF and above. More about antennas here: www.sdrplay.com/antennasuggestions/

We hope to release scanning software in the next few weeks (next release of SDRuno)

Baluns do add additional benefits with matching but the improvements are secondary to what you get by having a good ground when using wire antennas.

You are right... although it is of secondary benefit. :-)

@@SDRplayRSP True, it only becomes important when you have a transmitter, and start to worry about SWR.

Yes - metal pipes and radiators can be good if they are not close to noisy mains wiring AND continue as metal for a substantial distance (to act as a counterpoise). Even better, if you are close to the ground then a direct pipe connecting all the way to the real ground could be effective. For safety reasons you shouldn't connect directly to the mains wiring ground ( again, if this is a direct and short route to a purposeful ground stake it technically would work but would be prone to electrical noise generated along the way !) The ground (earth) pins on you mains wiring are there as a safety feature and a fault condition could cause the ground to become live! (e.g. no RDS and a grounded metal appliance has an internal short to live. A more expensive soultion is to consider an active magnetic loop - these are so much better at reducing electrical interference pickup. Check out other videos links on antennas here: www.sdrplay.com/apps-catalogue/

I use a counterpoise for both receiving and transmitting in my 3rd floor apartment.

The question about using the household ground is an interesting one. Yes, it's true that in certain houses a domestic ground might also serve as an amazing RF ground for HF (imagine you are on the ground floor using a mains socket ground terminal, very close to the consumer unit which in turn is anchored to an excellent ground stake also tied to metal water pipes which go underground etc etc.) However the safe answer is DO NOT CONNECT THE RSP DIRECTLY TO THE HOUSEHOLD WIRING MAINS GROUND TERMINAL! This is because under extreme circumstances a fault condition could exist in the household wiring whereby the safety ground temporarily gets an elevated high voltage on it (e.g. a wiring fault, a badly wired plug, a faulty appliance which uses the ground terminal - agreed it's highly unlikely when you also have current residual current detection circuits to ensure live and neutral current flows are equal and so few modern appliances rely on the ground terminal, but the safe answer is not to try it Additionally, an average ground connection to a mains socket, well away from the consumer unit and house ground, now has the potential to present significant noise, coupled capacitively, from the long lengths of parallel conductors where many sources of interference may be present from all the other electrical devices in the house). Regarding the question about transmitting with such a crude antenna: the main problem would be inefficient RF coupling of the transmitted signal. When receiving it doesn't matter that the antenna is not matched very well to the receiver. Receiving is all about getting the maximum ratio of signal to noise. There are a number of tricks you can play, but matching isn't important. What matters is that you collect more signal than you collect noise. I saw a post from N3OX who put this well and I quote " Most of the time, on HF at least, you have plenty of signal available from any random antenna you put up to not have to worry about losing power in the feedline or antenna system. The only way the RX will suffer is if your feedline or antenna is SO lossy that the signal you want to listen to drops into the internally generated noise in your receiver. This happens all the time on VHF/UHF, but on HF, it's usually the atmospheric noise or your neighbors plasma TV that keeps you from hearing well. Feedline attenuation and antenna loss just make the signal AND the noise weaker, but the signal-to-noise ratio stays the same. A high SWR on your receiving antenna just doesn't matter very much. It might increase your feedline loss by three or four dB, but it doesn't have much effect on your ability to hear. When you're TRANSMITTING, though, efficiency and gain are what you want. You want to transmit all of your power. That's because when you make your transmitted signal stronger, the signal to noise ratio on the other guy's end gets better. His noise stays the same, your signal goes up, you're easier to hear. If you have a high SWR on your transmitting feedline and get three or four dB of loss, you're three or four dB weaker at the other end. No good" (end of quote) So you could add a matching unit (ATU) between the RSP antenna socket and the crude antenna to ensure maximum transfer of tarnsmitted power into the crude antenna, but even then - if the foliage was at all damp, there's a chance for the high voltage RF nodes on the antenna to arc across and instantly cause a mismatch and potentially damage to the transmitter. But these are great questions - to get more complete answers, join the SDRplay forum and post them on www.sdrplay.com/community/viewforum.php?f=8&sid=839a6730d559764abf4afd8ada4932af - you can also do a search to read other related posts on SDRs and antennas. N3OX reference article: www.eham.net/ehamforum/smf/index.php?topic=32467.0

@@SDRplayRSP fantastic info and thanks. I've been working to wrap my head round HF antennas and this has been tremendously helpful.

Laeeq Khan Not a good idea as too close to mains likely to introduce hum