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
antennas.
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.
Fred/W8HDU
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