Tube Technology Unisys help required

[falcoron]

Would anyone have a schematic for the preamp board of this integrated amp ir the capacitor values?
Mates amp popped a tube and took out some of this board

 

[Juancho]

Can't you see from the other channel?

 

[falcoron]

Can't you see from the other channel?

He has it with a guy to repair and he is looking for this info. I’m only the carrier pigeon

 

[Juancho]

He has it with a guy to repair and he is looking for this info. I’m only the carrier pigeon

Understand. I've repaired / rebuilt a few of those and only ever seen a schema drawn up for the power amp. But if a tube went in the pre it should only have taken out the cathode bypass caps so I can't see why the repairer can't see the value on the cap. It's all standard fare. Also if eg V1 blew, the caps are the same on V2

 

[falcoron]

Understand. I've repaired / rebuilt a few of those and only ever seen a schema drawn up for the power amp. But if a tube went in the pre it should only have taken out the cathode bypass caps so I can't see why the repairer can't see the value on the cap. It's all standard fare. Also if eg V1 blew, the caps are the same on V2

Yeah agree, not sure why he can’t see the values maybe the print is gone? Dunno!

 

[Jazid]

Seems to me these things go up in smoke after a certain point. Maybe divining the past through charred remnants isn't this EEs skill?

 

[falcoron]

Seems to me these things go up in smoke after a certain point. Maybe divining the past through charred remnants isn't this EEs skill?

Maybe!
My brother had one for donkeys years and never an issue. Mates one was bought used about 20 years ago. I had the sig version about 15 years ago and kept a fair while and loved it.

 

[Juancho]

Maybe!
My brother had one for donkeys years and never an issue. Mates one was bought used about 20 years ago. I had the sig version about 15 years ago and kept a fair while and loved it.

Great amps, but as standard biased a bit too hot. Also the PCBs can short internally causing fun! The input stage is normally bullet proof but of course can't allow for a rogue valve shorting. I had plenty of shocks from these as there's no bleed across the PSU caps on the pre, with a live track right at the edge of the PCB which is all too easy to touch oh yeah, and on the pre board the cap polarity for the PSU caps is marked incorrectly.......

 

[Jazid]

Great amps, but as standard biased a bit too hot. Also the PCBs can short internally causing fun! The input stage is normally bullet proof but of course can't allow for a rogue valve shorting. I had plenty of shocks from these as there's no bleed across the PSU caps on the pre, with a live track right at the edge of the PCB which is all too easy to touch oh yeah, and on the pre board the cap polarity for the PSU caps is marked incorrectly.......

If that's your definition of a great amp I'd hate to see the state of the circuit board in a bad one