[Moon] LNA without protection relay

[Koellner, Guenter (NSN - DE/Muenich)]

Hello,

probably you know that I am currently preparing 9cm EME.

My problem is what to do with the feed and preamp. I have a C-Band-LNB, which has a FHX35 1st stage, that might fit perfectly. Just adding a septum and modifying the rear wall as well as adding a TX connector, and it would be ready. The problem is if the crosstalk from 50W on TX can destroy the FHX35 or not.

Otherwise, I would need to make a complete feed and even worse, I would need an external preamp. Feed is not the problem, I found matching alu tubes just recently, but I hesitate from the preamp, because every design that I have found is simply too expensive for my budget (DJ9BV, DB6NT) or not available (WB5LUA).

RW1AW or was it RW3BP who has shown improvment of the crosstalk with a small disc, might that probably be the solution, or is there any other chance to get that solved without a protection relay? Probably driving the gate down to -2V on TX?

73, Günter (dl4mea)


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