What kind of rectifier diode is this?

chris_d · Post by **chris_d** » 15 Feb 2008, 21:15

It is in a Zenith FM tuner that i took apart a while back. I am looking to use the PT from it for a tube preamp, and trying to figure what the PT's ratings are roughly, B+ wise.

What kind of diode is this? Can i assume that it has the same voltage drop characteristics as a more "normal" silicon setup like with 1N4001s/1N4007s?

Any information would be appreciated.

Thanks!

-chris

analogguru · Post by **analogguru** » 15 Feb 2008, 21:25

If we are talking about the green one, this is a selenium-rectifier.

smells bestialic if overloaded....

analogguru

chris_d · Post by **chris_d** » 15 Feb 2008, 21:53

analogguru wrote:If we are talking about the green one, this is a selenium-rectifier.

smells bestialic if overloaded....

analogguru

Thanks! Do you know what the voltage drop characteristics are for one of these, compared with a silicon diode?

I have only a very low quality schematic for this, and it is difficult to read the voltages that are listed. It appears to be showing 130v after this selenium diode. Could it be assumed that the PT was providing roughly 90vac? Or is the drop different in the case of these diodes?

-chris

KHELSTROM · Post by **KHELSTROM** » 15 Feb 2008, 21:57

analogguru wrote:If we are talking about the green one, this is a selenium-rectifier.

smells bestialic if overloaded....

analogguru

Not only dose it smell bad when it fails, the vapors it releases upon failure are toxic!

Stay away from these!

chris_d · Post by **chris_d** » 15 Feb 2008, 22:24

KHELSTROM wrote:
analogguru wrote:If we are talking about the green one, this is a selenium-rectifier.

smells bestialic if overloaded....

analogguru
Not only dose it smell bad when it fails, the vapors it releases upon failure are toxic! Stay away from these!

Thanks, I have no intention of using the selenium rectifier for anything, but i am trying to determine the specs of the PT that was attached to it. Are its voltage characteristics the same as those for silicon diodes?

-chris

analogguru · Post by **analogguru** » 15 Feb 2008, 22:57

A google search will show up this results:

http://en.wikipedia.org/wiki/Metal_rectifier

http://209.85.129.104/search?q=cache:vg ... d=74&gl=at

http://yarchive.net/electr/selenium_rectifiers.html

http://www.freepatentsonline.com/3694908.html

http://www.angelfire.com/ma2/AdamVon/resto1.html

analogguru

chris_d · Post by **chris_d** » 15 Feb 2008, 23:06

analogguru wrote:A google search will show up this results:

http://en.wikipedia.org/wiki/Metal_rectifier

http://209.85.129.104/search?q=cache:vg ... d=74&gl=at

http://yarchive.net/electr/selenium_rectifiers.html

http://www.freepatentsonline.com/3694908.html

http://www.angelfire.com/ma2/AdamVon/resto1.html

analogguru

Thanks! For some reason my google searches didn't lead me to any of those pages!

So i should expect more voltage out of this PT with a silicon rectifier. Good!

Thanks again!

-chris

analogguru · Post by **analogguru** » 15 Feb 2008, 23:23

The curve is much smoother than silizium.
So replace this rectifier with si-diodes and use the selenium for the next toobscreamer/distortion+ variation.

but keep this secret..... bootweakers could steal this idea for the selenium-overdrive.

analogguru