[TenTec] Ten Tec 238 coupler and 160 meters

[Steve Hunt]

Interestingly, when using *short* lengths of coax the loss can be lower 
at high SWR than when it's matched. For example, 10ft of RG213 has a 
matched loss at 1.9MHz of 0.03dB; but terminated with 500 Ohms 
(SWR=10:1) the loss is only 0.012dB - less than half. For a 2500 Ohm 
load (SWR=50:1) the loss is 0.046 - only 50% above the matched case.

It's only true for high impedance loads and short lengths, where only a 
small portion of the standing wave pattern exists; but they could be the 
conditions in this case.

Steve G3TXQ



On 09/11/2013 21:10, Carl Moreschi wrote:
> How much coax did you add?  The main idea of open wire line is it is 
> much less lossy than coax at high SWR's.  You therefore want to keep 
> the coax portion is short as practical.  The SWR on the feedline could 
> be 100 to 1 or even higher.
>
> Carl Moreschi N4PY
> 58 Hogwood Rd
> Louisburg, NC 27549
> www.n4py.com
>