Shorted rectifier & blown internal fuses in HH VX-150 amplifier

[Old Sparky]

This is the first HH amp*. I've had any dealings with, TBH, although over the last dozen years or so, I've repaired diverse makes including NAD, Cambridge, Pioneer, and others. My feeling is that the fuses failed because the rectifier went almost completely s/c, though I'm not certain what caused said rectifier to fail. The PSU is a conventional linear dual rail supply. DC voltages aren't specified on the diagram, but, as the smoothing caps. (2 x 4700uf in parallel on each rail ) are rated at 50v, I wouldn't expect the supplies to be more than 45-0-45v. Max A.F. o/p is quoted as 80W per channel. What I can obviously do before fitting a new rectifier and fuses is to measure the AC voltages on the center-tapped secondary. I'd expect these to be of the order of 28 to 30v (i.e. nominally 28-0-28v) if my (educated) guess of the DC voltages is correct. I'll watch out for the DC offset if I power the VX-150 via a lamp limiter!

*The local post-production studio who brought this one to me have 3 of them, I'm told, so I may be seeing the others in the future!