Thanks for reading this posting.

I need some help from experts. My TS-830S stopped transmitting. It was
working fine until few months ago, then it shows a little delay on transmit.
When I pressed PTT, the first couple of seconds get cut off in the
beginning. After this point, everything seems working fine with good power.
I thought it was caused by faulty driver or final tubes, so I replaced all
three tubes. After I replaced all three tubes, the symptom disappeared but
I ran into a new problem.

I was turning the TC1 trimmer to neutralize the final, and I saw a small
sparks and smelled some burn. From this moment, no output power. When I
turn the meter to Ip, it goes to infinite on transmit even if I try to
adjust it using the BIAS pot. The voltage on the plate seems OK.

Does anyone know what the problem might be? I think one of resisters or
caps got burned but I can't see it since the board is under the chassis.
Should I take it apart and check it out?

Any input will be greatly appreciated. Thanks.

Chris VA3UT