USA 5150.. with step down converter (200 Watt one when the amp can peak at 400 Watts so used my own step down transformer!Preamp tubes within chassis (on a rather flexible PCB not ideal for pushing the valves home)Fairly neat board a lot of ribbon cables buiBias mod noted (usually done to make the tube run a bit hotter) in the end I had to remove this to get her running well!Right way around ready to put the valves back in the power tubes are fine a few of the preamp tubes are worn but OKMmmm… no earth.. not running it like that!DIY earth lead (feel a lot safer now!)Well tested her out and measure bias.. OK on one side other side red plating! and making popping noises! see notes as to what was wrong all good now! Peavey 5150 in for a service as it was not working well…
Several things found
1) No earth to the amp! Potentially lethal with a tube amp I will not let the customer take it home until I have put a 3 pin plug on it!
2) Using a 200 Watt step down transformer for a 400 Watt power consumption ampis not good (but fuse did not go so unless he goes no louder that he has previously I guess he is OK) I used my own supply
3) Bias had been modified to run the tubes hotter and this was the main cause of the problems the customer had been experiencing, once back to stock all was well.
4) Full service given a pretty nice sounding amp!
Great sounding amp for metal, could not stop playing her!