Thread: Parallel coax
View Single Post
  #7   Report Post  
Old September 27th 15, 04:46 PM posted to rec.radio.amateur.antenna
Wayne Wayne is offline
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 409
Default Parallel coax



"John S" wrote in message ...

On 9/26/2015 2:24 PM, Wayne wrote:


"John S" wrote in message ...

On 9/25/2015 4:31 PM, Wayne wrote:
I use a short vertical antenna that has a low feedpoint impedance.

Would there be any advantage to running two parallel 50 ohm coax to
reduce losses to the shack tuner?


If your antenna is 25+j0, paralleling two 50 ohm coax lines would
reduce the SWR from 2:1 to 1:1.


Is that what you want to know?


Yes, more or less. But, I wouldn't even bother trying to reduce a 2:1
unless the rig wouldn't tolerate it.

The antenna feedpoint impedance is around 20-j130 at 14 MHz,
approximately a 21:1 SWR.

Some years back there was a discussion on paralleled coax, and I seem to
recall that it wasn't considered to accomplish much even under ideal
conditions.


# Oh. Well, then, it won't help. Are you opposed to putting an L and a C
# up there at the base?

Yes I'm opposed to that, but not for technical reasons.
It's a problem of an old man on a ladder