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EM34

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Forum » Valves / tubes - Semiconductors » VALVES/TUBES / SEMICONDUCTORS in RADIOMUSEUM » EM34
           
Onno Massar
 
 
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23.Aug.05 00:06

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Reply  |  You aren't logged in. (Guest)   1 Hello Ernst,
The indicated first production year of the EM34 in the valve should be corrected.
I have 2 radio's that use the EM34 that are older:
a Philips BX560A from 1947, the model was first produced in 1946.
a Philips (GB) 170A/15 from 1946.

Regards,
Onno Massar
Ernst Erb
Ernst Erb
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23.Aug.05 10:04

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Reply  |  You aren't logged in. (Guest)   2 Dear Onno
Thank you very much for your comment. I have changed the date of the EM34 to 1946 - just on ground of this model of yours. One can see only very limited usage in models in 1947 and 1948 but a sharp rise in 1949. Time will show if 1946 is really correct. I have also seen sets with the EM34 for much earlyer sets (with two question marks) and corrected either the magic eye to "unknown" plus text or found the correct but later year.

Only by such remarks of guests or members we can gradually find errors. Thank you.
Onno Massar
 
 
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23.Aug.05 22:34

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Oops, the BX560A has an EM4 not an EM34.
Onno

Jacob Roschy
Jacob Roschy
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29.Aug.05 16:07

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From 1938, Philips and Mullard (owned by Philips) started to supply Great Britain with valves of the so-called "Red Series", but fitted with the American Octal base instead of the side-contact base, as usual in continental Europe.

 

The type number was formed by adding 30 to that of the corresponding side-contact valve. The side- contact EBC3 became the Octal EBC33, the EF9 became the octal EF39,
as well the EM34 became the octal version of the EM4.


Since the EM4 appeared in 1939 in continental Europe, it is most likely, the EM34 appeared at the same time in the UK, but not yet in continental Europe.

 

As the Rimlock series appeared, the EM34 was allocated as tuning indicator to the Rimlock valves. So it is very likely, in continental Europe the EM34 was first found at radios fitted with Rimlock valves in the later 1940s.

 

Best regards,

Jacob Roschy
  
rmXorg