The Gun Counter

Old shipmate posted to me saying he needs to calculate return loss of an antenna. It's three separate antennas through a 3 -way diplexer, one coax cable. I forgot all that stuff 20 years ago. Not sure if it's a predictive/modeling thing or if he's got a setup now that he can actually instrument and measure.

VSWR = rtn loss in db, si?

Here are a couple of on line calculators he can use, along with some discussion of how to derive it:

http://vk1od.net/calc/tl/tllc.php

http://www.saarsham.net/coax.html

When I get home I'll try to dig through my antenna books and see if I can come up with anything else

Some additional information from the ARRL web site:

http://www.arrl.org/files/file/Technolo ... 106037.pdf

http://www.arrl.org/files/file/Technolo ... qex044.pdf

Hope these help