Hi all, and a Merry Christmas🎄🎄
I'm looking to replace the bridge rectifier on a Rotel 920ax amp. Currently it's a pbp206, which is no longer made, and as I understand it needs to be improved upon in this amp, as Rotel's have a habit of eating their rectifier.
What would be a suitable option that can be relied upon in the long term.
(Have attached the service manual)
Thank you all in advance 👍
Seasons best wishes to all 🎄🎄🎄
I'm looking to replace the bridge rectifier on a Rotel 920ax amp. Currently it's a pbp206, which is no longer made, and as I understand it needs to be improved upon in this amp, as Rotel's have a habit of eating their rectifier.
What would be a suitable option that can be relied upon in the long term.
(Have attached the service manual)
Thank you all in advance 👍
Seasons best wishes to all 🎄🎄🎄
This should work and fit the board, and can have a bolt-on heat sink added to it. Higher current too.
https://www.mouser.com/ProductDetai...Pqwp1t5WS8fz8WV4rbv7baf4Cpu0OIxhoCsgwQAvD_BwE
https://www.mouser.com/ProductDetai...Pqwp1t5WS8fz8WV4rbv7baf4Cpu0OIxhoCsgwQAvD_BwE
The obsolete PBP206 was rated at 600V and 2amps cont current. Anything above that will be fine. The one that rayma linked to would be perfect - probably even the same pinout.
The world is good every day, it's just some people that are bad.
They must have made the "new guy" spec that rectifier.
They must have made the "new guy" spec that rectifier.
No, the fuse protects the circuit after the fuse, an uprated rectifier will make no difference to the fuse rating.
Rectifiers can take significant overload for many seconds before damage. They dont blow “instantly” like transistors can.
It was a joke. An old-old joke. $7 semiconductors blow to protect $0.15 fuses.
(In this case the fuse is sized for the transformer. It is generally futile to 'protect' semiconductors with fuses, even moderately haft junctions like rectifiers.)
Yet this rectifier has died. In the 1970s I would spend an hour computing stray resistance on the rectifier time-curve. Today I just double or triple the rating of the failed part. (If I don't know which spec failed, voltage or current, I'd go up on both. This circuit "needs" 116PIV, and 3X is 400V, but 600V and 1000V are the same price. On test-bench this amp might suck 2.2 Amps, so 2A was cutting it very fine, so I would want to triple, say >6.6A. Rayma is pointing at very affordable 8A parts.
(In this case the fuse is sized for the transformer. It is generally futile to 'protect' semiconductors with fuses, even moderately haft junctions like rectifiers.)
Yet this rectifier has died. In the 1970s I would spend an hour computing stray resistance on the rectifier time-curve. Today I just double or triple the rating of the failed part. (If I don't know which spec failed, voltage or current, I'd go up on both. This circuit "needs" 116PIV, and 3X is 400V, but 600V and 1000V are the same price. On test-bench this amp might suck 2.2 Amps, so 2A was cutting it very fine, so I would want to triple, say >6.6A. Rayma is pointing at very affordable 8A parts.
600 and 1000 volt versions drop a couple tenths of a volt more.
I only use three sizes of full wave block rectifier. 10 amp, 35 amp, and 50 amp. 10 amp in the SIP for all low to moderate power, 35 amp square metal case with the 1/4” fastons for almost all power amps, and the bigger 50’s when I really really really need it. 600 volt unless I get a special deal on the 1000’s.
I only use three sizes of full wave block rectifier. 10 amp, 35 amp, and 50 amp. 10 amp in the SIP for all low to moderate power, 35 amp square metal case with the 1/4” fastons for almost all power amps, and the bigger 50’s when I really really really need it. 600 volt unless I get a special deal on the 1000’s.
Simple thumb rule, put the next higher rated, easier available part rated at least double the maximum rating, that means, if the amp is pulling 3.5 amps, you need 7 on the device, not available...so 8 or 10, whichever is sold in larger quantities.
600V is enough on a 110V or even 220V line, 1000 is over kill, but sometimes it is the part that sells more.
And do use the better quality ones, labor is more expensive than the parts, even your own effort costs time at least.
Do it once, do it right.
600V is enough on a 110V or even 220V line, 1000 is over kill, but sometimes it is the part that sells more.
And do use the better quality ones, labor is more expensive than the parts, even your own effort costs time at least.
Do it once, do it right.