Hi reflectees !
Doug,NX4D, has an interesting approach for the protection of the RX front end.
But it still has an evil problem to it. If the diode bias goes,so does
protection ! Additionally, transient voltages are abundant with long antenna
wires all the time and can easily kill even hefty PIN-diodes in no time at
all.This is why i always recommend to skip extra elegant devices,which produce
extra elegant problems. The only foolproof way is, to avoid the return of Your
own RF energy into the radio ! However clever u set it up with the RX jack- if
things fail - You gonna see a big bill - after You havent seen Your radio
probably for a long time. Another good idea is to avoid any unnecessary
semiconductors in situations/circuits where they can easily be replaced by a
single relay, an external filter-preamp switching unit is such a gadget with no
comlexity at all.
If the big bucks that You have put down for your radio are at stake, the least
critical components ought to be used in the most reliable manner.Aviation
engineering is always that way.
Good luck homebrewing de wolf -df2py-
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