Radio SWR When Used with PGXL

Russ Ravella

My setup has a PGXL after my 6700, then TGXL then Antenna. My usual antenna is a SteppIR BigIR vertical. It tunes quite well on all HF bands from 40M up. The highest native SWR (tuner bypassed) I see is about 1:1.45 on 20M and by 15M it's low enough that I have the tuner set to bypass from there up. This is measured with a Telepost LP100a between the TGXL and antenna, and the TGXL and PGXL measurements pretty much agree.

However, what I DO see is the SWR shown by the RADIO creeping up a bit with higher bands. It's never super high - about 1:1.7 on 6M - but since the radio is looking directly into the input circuits of the PGXL (which I assume are designed to present 50 Ohms at it's input), I would expect the radio's SWR to be much lower than that.

Is this normal ?

Thanks ! Russ KR6W

Erik Carling EI4KF

This is an interesting observation that needs an answer. I too get the same rising SWR on the radio as the frequency band gets higher. This is into a different amplifier than Russ, an Acom 2100S. On 6m the radio reports 1:1.9

Using an Icom 7100 into the Acom does not exhibit the same rising SWR, in fact it is flat about 1:1.1 on all bands.

After the amp, for these measurements, I have a dummy load whose native SWR is 1:1 on all bands.

So something about my 6400M is similar to the 6700 described by Russ. For me it is not a big deal but does strike me as strange.

Mike-VA3MW

I created a support ticket for Russ.