Startup problems

[Attilio]

One thing you can try is connecting the amp to a different speaker, or removing the chassis from the amp, to verify weather or not vibration is causing the problem.

--mark

I already tried it. My 18 watt is a head, and it makes these noises even if I put it on the floor. I think I'll try to change filter caps one more time...
Thank you.
Bye

[Attilio]

Hi guys, today I tried putting a 30V zener diode on the PT ground tap...
Now I have 354V out of rectifier, and the tremolo works well!!! Maybe the voltage was too high for the tremolo tube to work properly... I don't know. I always have the same noise from the filter caps, tomorrow I'm going to order them, I will try to change them. Anyway for a few minute, until the filter caps start to crack, the amp works very well, I'm very satisfied! I have to thank you very much for your help.
Bye
Attilio