Low voltages in 1972 Orange Graphic 80

[Gaz]

Just picked up this head today for $200 No head box though.

It actually sounds 'fine' to my ear, but the voltages are suspiciously low. The schematic says there is 180vac coming off each leg of HT winding of the PT. I have confirmed this, so I know the Pt is okay. From the bridge rectifier I am measuring only 268vdc. All the voltages at the tubes are low, of course.

I'm estimating I should be getting about 430vdc B+ under load. I've never worked on or built an amp with a bridge rectifier, but I'm guessing the problem has to be there, correct?

Any ideas as to why the B+ is so low would be very much appreciated.

Thanks,


Alex

[Gaz]

I'm an idiot. I was grounding my meter to the junction of the series main filter caps instead if ground The plate voltage is now 539 unloaded