Quote:
Originally Posted by pa24
I have another stupid question - how do you measure the db signal loss between antenna and receiver?
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Definitely not a stupid question, but I sure can't give you a smart answer. At work, we use an outrageously expensive piece of equipment called a "network analyzer" (our particular model costs over $150,000). A cheaper solution is a signal source and a power meter, but that's still way more than anyone here would spend. Without asking around, I would venture a guess that a good avionics shop would have enough stuff to kludge this measurement.
I can think of a way to do it if the GPS has a built in signal strength meter, but it would involve needing the GPS on a bench in clear sky view. Since I don't know if the minimum loss spec on the cable is related to damage levels (I doubt it, but I'm not going to risk someone else's GPS) I'm not going to post the procedure that's in my head right now without trying it first.
Cheapest solution is to look at the loss spec for the particular coax cable you have and hope they measured it right. These are usually given as dB / ft or dB / 100 ft. Adaptors and connectors will add probably no more than a couple of tenths of a dB to the cable's loss.