# ZENER DIODES



## Claudie (Oct 13, 2011)

Is anyone familiar with these? They all have Gold plated legs. The center row appears to be completely Gold plated. Has anyone ever recovered the Gold from them or does anyone know the value of them?

Link to the PDF: http://pdf1.alldatasheet.com/datasheet-pdf/view/76064/MICROSEMI/1N2837B.html


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## johnny309 (Oct 14, 2011)

They apear to be aluminium....and I see no reason to gold plate(only for legs) this because gold platting is used for good electrical connection .
They may have gold wire connection inside,but ...if are working parts ...you have to sell it(more money this way).


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## dtectr (Oct 14, 2011)

Ones this old are steel bodies, not aluminum. The exterior gold-plate would be for avionics/communication/military apps. 

Cut or grind open the top - there is usually gold plate inside, as well. I have a pic, somewhere. I'll post it when I find it. 

If you have a BUNCH, set up a jig to open with ease. These would be perfect for cyanide-processing, I think, which is beyond my present scope. LOTS of steel to digest, otherwise.  

Anyone know of a more economical way to process?


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## Geo (Oct 14, 2011)

ive done quite a few and they all seem to have nice gold, i just toss them in my AP batches. ive even found some that was painted black on the bottom so keep an eye open. not all are steel bodied,some are copper bases with stainless caps.


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## NoIdea (Oct 14, 2011)

Hi Geo - to remove the top, place upside down in a vice, crimping only the top, worked for me.

Deano


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## Claudie (Oct 14, 2011)

After disassembling, would the be a good candidate for the Gold cell?


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## element47 (Oct 14, 2011)

A "1N" prefix indicates a diode. A "2N" prefix is a transistor, and those "MJ's" are either transistors or Darlington transistor pairs. 

There might be gold plated pins coming out of the bottoms of these devices, but I would be very surprised to find the cases composed of anything but aluminum or steel. And if the case appears gold, I would bet it's anodizing. The difference in weights between the steel and aluminum cases is obvious even to the bare hand. The steel ones have more square corners on the case, the aluminum ones are lower profile. The single one on the far right of your pix *might* have gold plating on the flanges.


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## Claudie (Oct 14, 2011)

They all have the Gold plated pins on the bottom. The one on the far right has a deeper, more golden color. I have been searching for what value these may have and I have found that I can purchase the golden colored ones for $6.00 to $10.00 each. They look pretty brassy colored, so I think you are correct about the anodizing. Thank you for defining the "1N 2N & MJ" for me. That will help me to identify the others.


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## macfixer01 (Oct 17, 2011)

Claudie said:


> They all have the Gold plated pins on the bottom. The one on the far right has a deeper, more golden color. I have been searching for what value these may have and I have found that I can purchase the golden colored ones for $6.00 to $10.00 each. They look pretty brassy colored, so I think you are correct about the anodizing. Thank you for defining the "1N 2N & MJ" for me. That will help me to identify the others.





You may find the link below useful. It's basically for cross-referencing different manufacturer's part numbers to their NTE generic replacement part. If you type in the part number at the top of the page it will tell you what NTE part number would replace it, and you can also look at a pdf document showing the typical function, performance specifications, package type, and pinouts. For example your 2N1557 is a PNP Germanium Transistor Audio Frequency Power Amplifier, and the MJ2267 is an NPN Silicon Power Transistor - High Power Audio Amplifier. When they used to give out the printed books it seemed like I rarely ever came across a discrete semiconductor that I couldn't cross reference. Strangely though the 1N2837 (with or without the B) doesn't seem to be listed. It comes up on Google though as a 50 Watt zener diode (Voltage Regulator). Unfortunately the cases on them do look anodized to me. The transistor at the far right of the photo though with the steel cap definitely appears to have a gold-plated base. Any that have gold leads should have some small amount of gold inside also. As Deano suggested crushing just the cap with a vice will tear it loose from the base. I use a pair of end cutters with wide jaws to do the same thing.

http://www.nteinc.com/index.php

macfixer01


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## Claudie (Oct 17, 2011)

I appreciate the time everyone here has gave, researching and helping to identify these for me. I was able to remove the cap from one of them relatively easily. I am thinking the pins will go in the cell pile and, after testing for Gold, the rest will go in the scrap pile. 
Thank you for all the help,
Claudie


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