Hello,
I've been reading the comments on the Arrow 11 Antenna regarding performance comparisons with the stock vs. commercial Duplexer's. I decided to find the designer and ask him, while not the scientific answer I was seeking it does give us some idea of what he was asked to design.
73, Pete, WB2OQQ
Pete; Well, 2.4 db of loss sounds like one that is a little high, but possible if you include the cables. I did this design over 10 years ago, and I hold no stake in Arrow or Duplexer production. I used surface mount components that made it so that it would fit in the handle. The losses form those are not as good a tuned up commercial duplexer with better Q's for the inductors. As with any project some one's idea is always better than the rest. I take it with a grain of salt, this was a fun project I did for AMSAT and hold no grudges on making it better. If you can come up with a better design with some of the stuff that is out there, Go For IT!!!
Best Regards
Charles,