Realistic Stereo 40/A Selenium Rectifier

[mcaddie7]

Hey all- starting a rebuild of a Realistic tube amp. There are a few tubes that need to be replaced, as well as the electrolytic capacitors. However, I noticed there appears to be a red selenium rectifier. I have limited knowledge on these, but I have read that aging rectifiers can become dangerous and possibly explode?

Below is a picture of the rectifier. What would be suitable parts for replacement? And any help with the wiring would be greatly appreciated. Schematic included

 

[TriodeLuvr]

That's a rectifier for two 12AX7 filaments. It can be replaced with a pair of 1 amp diodes almost any voltage rating. You would probably need to add a resistor in the center tap to bring the voltage back down after this change. Not sure I would do any of this if the selenium rectifier is still working.

Jack

 

[init4fun]

I have read that aging rectifiers can become dangerous and possibly explode?

I don't know where you read that, but I've been involved with the repair/maintenance of vacuum tube electronics for close to 60 years and I've never, not once, seen or heard of a selenium rectifier, or any other rectifier for that matter, in a piece of consumer electronics exploding. Now what a selenium rectifier can do on the rare occasion that it's overloaded by, for instance a shorted capacitor connected to it's output, is to protest by letting out a foul stench that smells akin to rotten eggs (a sulfur kind of smell). This I have personally witnessed and while yes, it's rather putrid, the smell of a shorted transformer ain't all that pleasant either. So ya make sure your caps are all good, and like Jack said, if the rectifier is working, leave it be.....