> Can anyone tell me the approximate loss for a PL-259 connector at 28 MHz?
Immeasurable without of lab instruments. In the hundredths of a dB.
> Also, does anyone know the approximate loss at 28 MHz for antenna
switching
> relays like the ones used in the Ameritron RCV-8?
I assume you have a RCS-8V.
In that case, the loss is Immeasurable without lab instruments. In the
hundredths of dB.
Even on two meters you can't measure the loss on a conventional power
meter.
The impedance "bump" of an RCS-8V is also immeasurable at HF through lower
VHF. Regular SO-239's are about 35 ohms or so impedance, and that can
"screw up" instruments that use return loss to measure attenuation.
PL-259's are not a problem, it is always the female that causes trouble.
> I ask because I'm planning to install more PL-259's and more relays for
> automatic two-radio switching and bandpass filtering, and am trying to
> anticipate the additional losses. With some rearrangement of the existing
> configuration, the basic switching adds 2 connectors, bandpass filtering
> adds 2 connectors and switching for amp sharing adds 3 more connectors,
for
> a total of 15. (The latter is an experiment: sharing an 87A between two
> radios with automatic switching, the idea being to take advantage of the
87A
> automatic QSY.) The switches will add four more sets of relay contacts
> (replacing the Ameritron with TopTen A/B and 1-of-6 switches.) If the
above
> loss-per-junction figure is right, I'm looking at an increased loss of
about
> .3 dB. Sound right?
No.
The bandpass filtering would be the worry. The connector loss would be
about nothing.
73 Tom
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