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Counterpoise with TX500

Posted: Sat Jan 06, 2024 6:18 am
by ab2ng
I've been watching a lot of Tom's videos on YouTube. I've noticed that when he uses an Elecraft he always connects a counterpoise to the radio. He often makes a point of talking about this in the video. But when he uses the TX500 he does not use one. Other than the obvious point that there is no convenient place to connect a counterpoise on the TX500, why does he use one with Elecraft radios and not on the TX500?

Or to put my questions another way, if the TX500 does not need a counterpoise why does the Elecraft?

Re: Counterpoise with TX500

Posted: Sat Jan 06, 2024 11:12 am
by SkipRD
I don't think that's right. It depends on the antenna, but if I recall correctly, he's never used a counterpoise with an EFHW (with any radio); several of the random wire antennas he uses have their own counterpoises (which would be deployed for all radios); his Chelegance antenna has its own radial (for any radio); etc. And in any event, I don't why whether an antenna would benefit from an extra RF ground would depend on the whether the radio is attached to an Elecraft or TX-500.

Sorry, this isn't very helpful. If there's a particular video that illustrates what you're seeing, maybe there's something that might explain the difference.

73 Skip K4EAK

Re: Counterpoise with TX500

Posted: Sat Jan 06, 2024 1:09 pm
by Andrew (grayhat)
if using an EFHW then you won't need a counterpoise (ok, a short one may improve radiation but it isn't mandatory), on the other hand, if using an EFRW (a so called "random") then you will need a cointerpoise to both improve radiation and matching through the necessary (in this case) ATU

If going fot an EFRW, a useful resource may be this

https://k7mem.com/Ant_End_Fed.html#Not_Random_Multi

but then I disagree with the idea of using a "T" type toroid for the 9:1, the reason is clear by looking at the following, start by looking at the curves of a 9:1 wound on a "T" type toroid

https://vk6ysf.com/unun_9-1.htm

now, compare them with a 9:1 wound on an "FT" type toroid

https://vk6ysf.com/unun_9-1_v3.htm

and I think that my point will be rather clear, then, since more often than not, the counterpoise system won't suffice, but we'll want the antenna, and not the feedline, to radiate/receive, we will also need to add something like this

https://vk6ysf.com/balun_choke_balun_hf.htm

on your coax, nothing special, but worth considering if you want to squeeze the max out of your "random", and then, since some lenghts are "mandatory", you may work on the counterpoise system to optimize match and radiation

HTH
.

Re: Counterpoise with TX500

Posted: Wed Jan 10, 2024 12:41 am
by ab2ng
Thanks for the replies, good information provided.

I think that he has only ever used verticals (which all have radials or counterpoises) and EFHW with the TX500. I don't think I have ever seen him use a random wire with the TX500. That would make sense since there is not really a good place to attach a counterpoise to the TX500.

Again, thanks for the replies.

73s
David
AB2NG