Actually, the loss from a "UHF" connector would be in the coax, not all
concentrated in the connector as I previously stated. I just got the
following private e-mail that nicely explained that:
"While I would concur that coax connectors, even the dated PL-259/SO-239s,
[UHF] are pretty good at HF frequencies, I think what "losses" they do
impose do not occur in the connector itself. Rather, they create impedance
bumps, which in turn cause reflections, which result in a standing wave on
the transmission line. Almost all the heating from this effect, therefore,
occurs in the coax, not the connector itself."
The heating due to the condition stated above would be distributed over a
longer length of coax instead of being concentrated right at the connector
itself.
But that's not what that one fellow (and all the others who have beat this
same drum over the years) implied. He didn't state a particular type of
connector, but rather lumped all connectors and switches together as all
being lossy. And that would include constant impedance connectors and
switches. Any heat from losses in a constant Z connector would be created
right at the connector itself.
In any case, it's been proven that the length of the impedance bump inside
the junction of a PL-259 and SO-239 is such a tiny fraction of a wavelength
below 200 MHz that losses from a mismatch is of no practical concern,
either for RX or TX.
73, Mike
www.w0btu.com
It wouldn't take hardly any loss at all for a connector, switch,
> or whatever to get warm fairly quickly when power was transferred through
> it. If it did have significant loss, you would burn your fingers on the
> connector at well below the 1500 watt level.
>
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