Curious, those extra small fins (on g2?).
I can't find those on the Philips, Mullard, Telefunken, RFT, Tesla, Chinese or Russian versions I have.
Are these recent or old production?
I can't find those on the Philips, Mullard, Telefunken, RFT, Tesla, Chinese or Russian versions I have.
Are these recent or old production?
Building the Shuguang EL34-B Vacuum Tube - Part 1 - YouTube
Screen cooling fin is mentioned in the above video.
Screen cooling fin is mentioned in the above video.
99% It is a Mullard (Philips family).
Typical Mullard are the; micas, the 'point' on the pins, the getter bowls, the anode 'slots' and welding. Some do have little 'fins' on the anode rods to stabilise the micas.
Is there a hole in the middle of the spigot?
Is there any evidence of lettering on the glass close to the black base?
Typical Mullard are the; micas, the 'point' on the pins, the getter bowls, the anode 'slots' and welding. Some do have little 'fins' on the anode rods to stabilise the micas.
Is there a hole in the middle of the spigot?
Is there any evidence of lettering on the glass close to the black base?
Your tube indeed shows several signs of having been made somewhere in the Philips group. As such there should be an etch code next to the phenolic base, as yet mentioned. Is it's pin #6 omitted?
Best regards!
Best regards!
All the pins are present and yes there was a near invisible code etched into the bottom of the glass B3H4.
Shining a flashlight on the glass there does appear to be XF2 above the previous code. Thanks everyone.
B = Blackburn factory
3 - 1963 or 1973 depending on revision number xf?
H = August
4 = 4th week