[Elecraft] K3S no RF at CW - Solved

[kismarian at hotmail.com]

I sent few emails and talked to David at Elecraft twice last week. He suggested probing RF at 2nd TX Mixer, which confirmed 0 RF on CW and full RF power on SSB.
I found out that on KREF3 board the high insertion loss >45dB of the wide-band TX crystal filter activated only in CW MODE caused the 0 CW RF Power.  Probably some of the crystal leads inside the can detached during transport. I bypassed it temporarily by turning the relay on as it is in SSB mode with thin wire between pins 2 and 4 of the KREF3 module. The K3S power calibrated then as expected. The filter could be there for extra purity of CW signal, so I will have to exchange the module for a good one.
I would like to extend my gratitude also to W, G and OM hams who helped me solve this problem with their personal emails.
73,
Marian, WS9M
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