After trying some different input circuits the conclusion was a series tuned circuit, with a 1 turn
link coupling. The coil is 3 turns with ~3/8 id. The coupling loop is about halfway meshed.
I found it at the project “2m AMP with 4CX800A by NU8I”
The amplifier will be tested in the upcoming DARC VHF UHF Microwaves contest next month.
*** NEW schematic of the RF-Deck and picture of the Cavity *** click here