Re: 75ohm Impedance question K3S and Antenna side.

Posted by Vic Rosenthal on Mar 31, 2020; 5:57pm
URL: http://elecraft.85.s1.nabble.com/75ohm-Impedance-question-K3S-and-Antenna-side-tp7659364p7659368.html

I don't think you need a unun because the additional loss due to SWR
running RG/6 at 2:1 is only 0.381 dB, and the unun itself would
certainly have some loss.
But the loss in 200' of RG/6 even at 1:1 is about 2.9 dB! That is almost
half your power. RG/8 would have only 1.9 dB loss, and with a probable
SWR of about 1.5:1 you would have a total loss of 2.2 dB.
Even better would be Belden 9913 or similar coax, which would give you a
total loss of 1.6 dB.
All these facts and more are available at
<https://www.qsl.net/co8tw/Coax_Calculator.htm>

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
CWops no. 5
http://www.qsl.net/k2vco/
On 31/03/2020 19:39, [hidden email] wrote:

> I'm about to pull the trigger on a Hustler 6BTV (6-Band, 80, 40, 30, 20, 15,
> 10 meters). It will be temporarily installed (with radials) about 200' away
> from my house. I'd like to run CATV "hardline" but I'm not sure how to get a
> 2:1 UnUn with a wide enough bandwidth on the antenna side (the impedance
> with 60ish radials should be in the 35ohm range). In addition I believe I
> will be ok on the RIG side to just connect RG6 (75ohm) to the hardline and
> direct to the rig since my K3S can match the impedance. Is this essentially
> correct and is there a better way to do this? I'm trying to minimize losses
> for the distance run and still have a decent transmitted signal.
> Thanks in advance.
> Yeah, I should know this stuff but I can't know everything 100%.
>
> 73 es
> De AE4PB
> ..
>  
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [hidden email]