>
> My GPS antenna is not just an antenna. It is a receiver. The signal
> on the wire coming out of it is data, not RF.
>
> This equipment now days is pretty much all digital.
I know they can now do that easily with a tiny $20, 12-channel GPS
receiver module in the antenna itself, but question if it's common yet
in aviation units. Which one do you have? My UPS/AT box isn't that
way, and I would theorize the cost and lead time needed for FAA
approval means that many of our devices are necessarily done the
relatively old-fashioned way with mere amplified antenna. But if your
case, good for the builder to know if more modern design. At the
limiting and meager baud rate the satellites do, who knows, even 10
feet of household "zip cord" may work! Else low-loss coax with
shortest run.
> 40% ?????
I weasel-worded as maybe up to 40% loss, but if mounted aft of the
baggage bay bulkhead, my data sheets on low loss cable could put ya
into the 30's easy. UPS/AT thus even allowed for up to 4dB loss, or
63%. I agree with your other point that it's all really moot here, no
matter what fancy circuitry is potted into an antenna mounted too near
a noise source.
Reg,
Fred F.
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