At 14:42 02 February 2016, shkdriver wrote:
Hey Group,
I've got a 1975 Std, Cirrus new to me. I am replacing the com radio and
in
=
the process I deleted a poorly done splice in the coax cable with a rg-58
s=
older end.
After the bnc end was installed, I measured the resistance between the
cent=
er and shield leads, I measured 0.9 ohms, thinking I had a stray shield
wir=
e or other problem, I removed the new bnc end and measured the bare end
of
=
the coax, still 0.9 ohms. Then I reinstalled the bnc end, same 0.9 ohms.
Does the special type of antenna in the tail has some weird ohm
value?
Using a handheld I wouldn't miss if it fried, I measured swr and output
wa=
tts, (using a MJF model 812B swr/watt meter)
watt output is 3-4, swr is 1.6-1.8 (in my garage, not ideal), Output
watts
=
are probably what the icom a-2 is putting out.

So, I'm not confident that the coax and antenna is safe for my radio,
every=
other coax and antenna combination I ever measured was infinity between
th=
e ground shielding and the center lead.

I'm using a decent blue point digital multimeter.

Any Thoughts?

Thanks
Scott W
You said 'splice', did you really mean a taped join? Surely not!

Such joints are suspect at best and rarely moisture-proof. Moisture can
capillary up the Co-Ax and give very poor performance. A quality BNC or TNC
connector will give a moisture-proof seal, but any moisture already there
will be trapped.

Can’t say specifically about the Std. Cirrus, but in some fins there is
not sufficient height, and the aerial needs to be electrically longer. This
may give a surprising DC resistance.

Using a DC metre to judge an antenna is always risky.

The results from the SWR test don’t look too unreasonable, considering
there is a length of co-ax in the way. True SWR needs to be measured at the
antenna, but this is not always possible!