Anybody worked on or with UREI 6500 amplifiers

[wattsabundant]

Every time you replace the fuse you do at least $50 more damage. With both output modules removed, bring it up with a 60 watt bulb or so and a 5 amp fuse. If successful discharge the caps and install one module and bring it up on a 100 watt bulb. If the bulb doesn't dim then switch to the other module. It's likely only one module has failed and you haven't done any more damage.

It would be helpful to add a photo of the back side of the modules.

 

[SirPaulGerman]

Every time you replace the fuse you do at least $50 more damage. With both output modules removed, bring it up with a 60 watt bulb or so and a 5 amp fuse. If successful discharge the caps and install one module and bring it up on a 100 watt bulb. If the bulb doesn't dim then switch to the other module. It's likely only one module has failed and you haven't done any more damage.

It would be helpful to add a photo of the back side of the modules.

I am not able to fix the amp, is going to my tech

The amp was very expensive back in the days
came out in 1981 for $2200
the Yamaha P2200 was $1100