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Who can explain the source of this Siemens 12AU7

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Who can explain the source of this Simense 12AU7

By change I got a pair of milliary coded Simense 12au7. Collecting tubes is one of my favorite hobby and I always endeavor to un-earth the real source of the collected tube as a pleasure. What suprises me is that this tube, coded as "1A1 G4B", with the "G" printed 90 degress from horizon.

I have checked the code list of the Philips Gourp, which shows that G stands for tubes made by Mullard Fleewood and after Feb 22, 1954, Loewe Opta, which seems to be a factory under Valvo.

But there no indication of such a horizontally placed "G".

Anybody knows the answer?
 

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Try posting a better picture, that might help. Pretty obscure question, the people who definitively knew the answer to your question are probably long departed this mortal coil.. :D

The other possibility is that they are recent knock offs by a clever tube counterfeiter. (Hopefully not though.) It has happened to me once, I bought some Amperex 12AU7A on ePay from someone in HK, markings and boxes absolutely perfect, tube though never saw the inside of an Amperex factory. I didn't pay a lot, but I still felt very cheated. They might have been recent Richard**n relabels, but they weren't billed as such in the auction.

You may already know more about tube collecting than a lot of people here.
 
Low possibility of counterfeiting

I am always traveling in the most under-developed countries where tube audio is a long forgotten tale and new fever for such fatanstic machines are at the stage of incubation, 'cause modern tube machines won't cost small.

This pair of tubes costs me less than US20, 00 or each less than US 10.00. I bought them from a local shop with a 50-year history.

Sometimes I can buy ECC82 at US 1.00 each. They need not to counterfeit for US 1.00 unit price.
 
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The EI plant in Nis most definitely still exists! Currently they are producing a variety of different types, before disseminating bogus information on this forum please why don't you do some research ? :xeye:

Here is a link or two, there are lots of others:

http://www.eierc.com/rc/products.htm

http://www.tubedepot.com/ei.html showing current production available stateside.

Also while EI makes a knock off of the Telefunken 12AX7A, the plant was licensed by Philips (and used mostly Philips tooling) to manufacture tubes starting in 1951. Today they specialize mostly in audio type tubes, and custom designs like the KT90/KT99.
 
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kevinkr said:
The EI plant in Nis most definitely still exists! Currently they are producing a variety of different types, before disseminating bogus information on this forum please why don't you do some research ? :xeye:

Here is a link or two, there are lots of others:

http://www.eierc.com/rc/products.htm

http://www.tubedepot.com/ei.html showing current production available stateside.

Also while EI makes a knock off of the Telefunken 12AX7A, the plant was licensed by Philips (and used mostly Philips tooling) to manufacture tubes starting in 1951. Today they specialize mostly in audio type tubes, and custom designs like the KT90/KT99.

agree with everything except with "Currently they are producing" ;

that can't be absolutely true ,unfortunately .
all I know is rumors about selling NOS and producing (if anything) just garbage.....
I hope I hope I hope that it's just rumor;
several other subsidiaries in EI concern are definitely kaput ,probably sold for pocket money.....mebbe if soon someone enough smart do the same with EI RC (toob house) ,fresh production can be true...........just imagine power triode in KT90 bottle!

edit:
quote from EI site :
"Last modified: 26.01.2003"

this is most recent date I found :bawling:
 
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They are actually building a new site, did not post a link to it because there is nothing more than a new logo there at the moment. The manufacturer's site hasn't been updated in a long time for sure, however all of the listed types are available.

My understanding is that there is new production, I have talked to several wholesalers here in the USA who have informed me that that is the case.

Also I have an acquiantance who has been the plant in Nis since the end of the war and he indicated it was quite intact.

Story of other divisions rings true and would be similar to experiences at the old Tesla facility as well as Svetlana SPB in St. Petersburg.. All former shadows of the state run concerns they once were.

IMO EI quality was never anything to brag about, my experience with power tubes like the KT90 was not wonderful. Their 12AX7 seemed comparatively short lived compared to nos USA and Western European types.
 
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Amperex built very good tubes at the Hicksville, NY plant, prior to the Philips acquisition and the "counterfeits" I bought definitely were not Amperex or any of the Philips sister companies. I suspect they were nothing more than relabeled Sylvania mil spec types made in the late 1980's just before the plant shut down. IMO nothing special and not worth anything close to what I paid for them. I was very disappointed to say the least.. :D

Amperex tubes whether US made or sourced from other Philips subsidiaries always had a what I think is a well deserved reputation for superlative quality. Early on in my career their 12AU7A (Dutch or German made) was just about the only one I would use, other than a French Mazda.
 
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