What kind of diode is this?

[mateusborges]

Not sure if this is the right forum, sorry if not.
Does anyone know what kind of diode is this? I can't find out.









Cheers!

[r080]

Looks like some sort of power diode.

[GibsonGM]

It's an 'electronics or electronics part related question', it's the right forum   

[italianguy63]

1N92?

[antonis]

1N92?

Ge diode with 635mV forward voltage drop..??

@mateusborges: measure leakage current..

[Rob Strand]

Diodes like that were common in the 60's.   One common one was the OA210 maybe Mullard/Philips.  Silicon power rectifier.  It was rated at 1A or so, somewhat less than what it looks like it could do.

I found this,  which says 0.5A,

https://www.web-bcs.com/diode/dc/oa/OA210.php?lan=en

There were others like that, perhaps from ITT with a different part number.

You might even find some electronics magazine from the mid 60s using these diodes in projects.

Here's an interesting thread discussing some of these diodes,

https://www.radiomuseum.org/forum/how_old_is_the_by100_rectifier.html

It mentions BY100, which is a similar looking device, and some others.  There was also an OA211

The number I remember is the OA210.  Later there were BY127 or something like that which were plastic packages with a rounded (hemispherical) end for the cathode, often green.

I don't know what the diode test current is on the TC-1 but the OA210 datasheet (Philips 1958) shows about 640mV @ 1mA and 790mV @ 10mA. [Sorry wrong graph]  635mV @ 10mA.

[mozz]

Pretty common, back in the day, late 50's early 60's. My dad used to bring them home on mil surplus circuit boards. I think they were all silicon thou i haven't tested too many. I have yet to put one in a circuit, maybe in one of those larger point to point pressed steel cases. They used to be called "top hats".

[Rob Strand]

Pretty common, back in the day, late 50's early 60's. My dad used to bring them home on mil surplus circuit boards. I think they were all silicon thou i haven't tested too many. I have yet to put one in a circuit, maybe in one of those larger point to point pressed steel cases. They used to be called "top hats".

That's a good stash.  I chucked out 99% of my old parts in the late 70's.  I remember those gold ones as well.

Come to think of it there were power zeners with these packages.   So there's a chance it could be a zener.   It would measure like a silicon diode in the forward direction and the only way you tell it was a zener is to test  it under reverse bias (which could be upto 40V or more).

Your gold 1N442's are 68V 1.5W zeners!

[PRR]

It's a DO-1 package in my old RCA book. Apparently JEDEC changed the number several times. I would swear it ran back into the Germanium age and was our all-purpose 1 Amp diode until good epoxy happened.

If you can't read the number, you can't prove what it was sold as. If you just want a distortion diode, throw it in.

[mozz]

[quote author=Rob Strand  Your gold 1N442's are 68V 1.5W zeners!

I kind of think maybe they were using them in place of voltage regulator tubes? Only a few ma's i guess. Some are about the same size with a threaded anode. They may hold a little more current.

EDIT: just tested about 20 pieces, 5 of them were germanium. I'm actually surprised. The silicon were all .600v to .630v on my dca55 and the germanium were .212v up to .235v. The black GE were more often germanium, date codes from *729 to *939 and the latest was a 4 digit 6226. Other brands such as Raytheon,Westinghouse, IR, were all silicon.

[mateusborges]

Heyas!

Thanks for the replies.

My TC1, in the zener measurement area, says it's not a zener, but then again it's just a cheap tool I'm not sure if it can read zeners correctly.

@antonis
I can generate a maximum of 24v DC atm, still haven't bought myself a good power supply, would that be enough?

@prr
Actualy trying to discover what to do with those, if there's any special kind of project that could benefit from those I'm definately saving 'em.

There's only 8 of these, all others were destroyed.


I extracted those diodes, along tons of other cool components, from a dead radio transmiter from a decomissioned university radio station, the radio was far from being able to get repaired =/

P.S: Couldn't find anything wrote in them.

Cheers!

[Rob Strand]

I kind of think maybe they were using them in place of voltage regulator tubes?

More than likely.  I can only guess they transitioned from regulator tubes to zeners to modernize.   I didn't have much to do with regulator tubes so I can't comment on the technical side.   No doubt the zeners let you set to voltage a lot more finely than a regulator tube.   Some old technology stuff I had used Neon bulbs for regulator tubes.  In some cases there were two in series with a jumper as coarse way of setting the voltage.

EDIT: just tested about 20 pieces, 5 of them were germanium. I'm actually surprised.

I'm a bit surprised as well but I only really remember the silicons (and zeners).  Like PRR said those packages were around early on.  I remember a ~1960 tube stereo with some black diodes like that.   They were used as power rectifiers and I just assumed they were silicon.

I extracted those diodes, along tons of other cool components, from a dead radio transmiter from a decomissioned university radio station, the radio was far from being able to get repaired

Yes, should have heaps of stuff in there.   Old equipment often has really good quality switches.

[antonis]

@antonis
I can generate a maximum of 24v DC atm, still haven't bought myself a good power supply, would that be enough?

No problem..

Apply 24V (or any other voltage supply) in reverse direction (from Cathode to Anode) with a series resistor of 100k (say) and measure voltage drop across the resistor..
e.g. for a 50μA leakage current you should mesaure 5V across 100k resistor..

P.S.
Ohm's law here stands for current times resistance so don't take into account supply voltage..