Need help determining ratings for rectifier diodes on a Supro S6625

[ewd]

I’ve got an old (60’s era) Supro S6625 amp in the shop. It came in with a dead short, blowing fuses. Found half of the bridge rectifier diodes shorted. Enzo most graciously provided me with a schematic to assist in identifying component values inside this 45-50 yr old amp. The schematic specifies the rectifier diodes as 355-1. The diodes actually present are identified with 1R R210 markings. Haven’t been able to find datasheets on either set of numbers online. Can anybody help with determining suitable ratings for replacement rectifier diodes? -I’m real weak in this area. The schematic indicates 320 VAC peak to peak out of the PT transformer, provided to the bridge rectifier circuit, and 370 VDC output from the bridge to the amp. (I would upload the schematic that Enzo provided me, but the forum is not cooperating peacefully this evening).

[JHow]

I'm not the guru Enzo is, but since you are in North Florida, I thought I'd post: why wouldn't just plain old vanilla 1N4007 work? 1000V 1 Amp? It shouldn't be much more of a question of the voltage that hits it and the current. 1N5408 is 1000V 3A, overkill but then you wont have to worry.

[R.G.]

Minimum, 2xB+, plus some safety vactor; not less than 1000V in any case. Actually, the pedestrian 1N4007 ought to work. A full wave bridge actually has two diodes in series, one on positive and one on negative.

Use a UF4007 fast/soft recovery for improved EMI characteristics.

[R.G.]

Simulpost.

[ewd]

Thx JHow, RG. I was thinking of the 1N4007, but didn't know if I should go up to the 3A 1N5408. If the 1A is sufficient, maybe I'll check to see if Mouser or someone else carries the UF4007.

[Enzo]

They are just dumb HV rectifiers, 1N4007 or equiv ought to work fine.

[52 Bill]

The original diode is an IR R210, made by International Rectifier. The ratings were 1000v 2A.

The 1A 1N4007 will be more than enough for that circuit.