Fairchild Diodes

[shrtrnd]

Trying to identify some older, glass, Fairchild diodes, is anybody familiar with this marking system?

GG901GG
GY918GY
GY929GY
GY930GY
GY035GY

I tried contacting Fairchild customer service, (E-Mail & Phone), Fairchild never responded.
Either the markings are proprietary, or so old the company doesn't maintain a data base on them.
Thanks

 

[Resqueline]

No response is no surprise, neither is not keeping data on old devices. Could be proprietary.
Numbers look more like a date code than a part number, & google turns out zilch.
The look of them might say someting about what type of diodes they are however.

 

[shrtrnd]

Yeah, thought I'd give it a try, to see if anybody's seen this before.
My best guess is probably old military designation.
I've got some similar diodes made by Motorola, with duplicate letter prefix/suffix,... and an obvious date-code in the middle.(1980's)
Thanks for taking a look at them anyway.
Betcha if I found an old retired Fairchild engineer who worked with these, he'd know the story.

 

[Resqueline]

If you're able to get a clear close-up shot of them I might recognize something about them.
Also, if you have a mulimeter you can test & compare them with known diodes. A diode test drop of 100-400 says it's a schottky, a drop of 450-650 say it's an ordinary diode, & a drop of 700-950 says it's a zener. It's unlikely they are germanium but those would have a drop in the schottky range. Knowing where they came from might say something. I guess the (duplicate) letters is the code but I never saw that kind of marking, even if I've seen some military types.
But a lot more about them can be found if one just has the equipment to test them.
Yes, I'm sure the needle in the haystack would know something. The internet is a great thing.

 

[shrtrnd]

Update from shrtrnd:
Still trying to track this down, but stumbled on interesting information for people like me,
who spend too much time trying to track down proprietary part numbers.
Philips Semiconductor Small Signal Transistor and Diodes MARKING CODES
http://matthieu.benoit.free.fr/cross/competitive/philips/SMD-PHILIPS.pdf
If I made a typo in the above address, I found it by Google-ing one of the Philips part numbers, and 'cross reference'.
It's a comprehensive list.
I actually responded to this Matthieu Benoit on this site quite a while back, but he was
in and out of here faster that I could get to him. He posts a lot of free cross references
for manufacturer parts on the web, Google him for cross references.
p.s.-when I posted this, for some reason, it left off the 'SMD-PHILIPS' and just printed "MD-PHILIPS"