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Hoffman Amps Forum image Author Topic: Fake Siemens GZ34 is actually mis-labeled Russian 5C4M  (Read 8147 times)

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Offline mresistor

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Fake Siemens GZ34 is actually mis-labeled Russian 5C4M
« on: January 14, 2018, 08:38:24 am »
GZ34 ?    Do these look like GZ34's ?  They look like 5Y3s to me because they are Russian 5C4M .


https://www.ebay.com/itm/2x-SIEMENS-MULLARD-GZ34-5AR4-ROHRE-NEU-IN-OVP-NOS-/322995819726?
« Last Edit: January 28, 2018, 09:46:04 am by mresistor »

Offline mresistor

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Re: GZ34 ??
« Reply #1 on: January 14, 2018, 11:25:18 am »
Pretty sure these are mis-labeled Russian military 5C4M/5U4M rectifiers.   Definitely not Mullard GZ34s like the seller says and not even new production Mullards. I have a USSR Sovtek 5U4M that is labeled as a 5Y3 that looks exactly like these.  They are closer to a 5V4 than a 5Y3 and also appear to be directly heated. Pity the 3 people that actually bought these thinking they are GZ34.

http://www.nostubestore.com/2012/01/russian-nos-gz34.html   


 
« Last Edit: January 28, 2018, 09:02:04 am by mresistor »

Offline mresistor

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Re: Fake Mislabeled GZ34 is actually Russian 5C4M
« Reply #2 on: January 28, 2018, 09:05:47 am »
Here are some being sold under National Brand labeled as 5AR4 but they are the Russian 4-pin 5C4M .  The details that give it away are 4 pins - round glass top - the flying saucer getter - 2 support rods - and different shaped mica spacer at the top of the plates. 

https://www.ebay.com/itm/263463293708?ul_noapp=true
« Last Edit: January 28, 2018, 01:07:56 pm by mresistor »

Offline mresistor

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Offline mresistor

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Re: Fake Mislabeled GZ34 is actually Russian 5C4M
« Reply #4 on: January 28, 2018, 09:16:27 am »
pic of fake

 


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