Frederick Vobbe wrote:
>With all due respect, Dan, in design you have to weigh all losses, and
>one way is not to over-complicate designs with multiple connectors.
>However, on my station I come out of the rig, to a low-pass filter, then
>to 4-port coax switch, then up to a Heath antenna switch, finally to the
>The dB/loss question came up and we debated it to death in our club,
>till one enterprising soul suggested we measure the signal levels. A
>station transmitted a carrier on 7, 15, and 28 mHz, and it was measured
>in the configuration above, and with a coax from the antenna direct to
>the rig. We ended up repeating the tests by dropping power to where the
>signal was barely detectable. The result was; while the loss through
>the system could be measured, and that measurement was very minimal,
>from the operator's chair there was no difference between (3) devices &
>(8) PL259 connectors, and a single RG-8 with (2) PL259 connectors.
>Now, if you're talking 6-meters and above, (especially 70cm and above),
>then there is a compelling argument for lessening PL259s in the design.
>But at that point I would be thinking of LDF50-4 or LDF50-5 with Type-N
>connectors to mitigate losses.
>Another critical component is length and quality of line, especially
>when line is cut and connectors attach with appear reflective. A lot of
>things weigh in on this issue, but all have to be considered.
>I'm not discounting losses in PL259s. But I think there is a time to
>knit-pick, and a time to lean back and operate.
Interesting thread. Loss (whatever you might think about its
significance) can be completely eliminated by doing away with the
connectors. Just grab some of that 'no-loss' coax I keep hearing about
and solder it directly into the circuits. No connectors, no loss, no
problem. Almost as good as mounting the rig on the mast with the rotator.
On a more serious note, has anyone ever tried doing that? Locating the
rig on the mast next to the antenna and operating remotely? This might
be easy enough to do with rigs that have detachable front panels.
I am not suggesting that this is a reasonable solution for an HF
installation but how about UHF.
TowerTalk mailing list