[Collins] 30l1 amp.

[ted]

I have a 30L1 amp, its been working great until today.I was using it today and both fuses blew. Replace again and same thing.I figured tube shorted. I thought if I removed tubes and defeated interlock just to see if fuses would blow.They did.!I had  replaced PWR supply board and all components a year ago and has been working just fine.I notice this morning while using amp swr would jump up while on ssb. But if I used lock key on 32s1 swr ok. Well there was some arcking when I moved load control. I cleaned capacitor plates where there was arcking.Would appreciate some input on what to check first. Thank you.