2E22 - "300B Pentode"
Kurt Steffensen
I think the mystery is solved.
2E22 IS a genuie PENTODE.!
I am 100% posetive about that.
I have carefully excamined the ones I have got.
I also now understands why it is refered to as the 300B,
pentode.
The similarity is remarkable.
This can´t hardly be any "accident".
Even the grid, and the filament, are the same structure.
The five weird WE300B, rings on the plate are even on
the 2E22 plate!
The electrode assembly in the 2E22, are however a higher
quality,simply because it is a modern tube.
(The 300B, being developed in 1928-33)
2E22 has smaller bottle than, the 300B.
Also the plate are not as tall, as the 300B.
But as the 2E22 is a 30Watt tube, it all makes sence.
The NEOTRON,made in France, is certainly a pentode.
(Nothing to form any beams are inside)
The other US, TUNGSOL, I can´t prove. (The micas are not
transparent)
But it is unlikely to me that it should be a beam-pentode.
The 2E24, and 2E26 are also reel pentodes...
Now, there is the possibility, that the ones made in US are
with beam-plates , and only the European ones are without...
The arguments for this could be the fact that US-manufacterers
did favour the beam-tubes, and that the EU-manufacterers mainly
produced pentodes.
But it is more likely, to me , that all the 2E22´s are simply
pentodes.
The nickname "300B pentode" has allways sounded wrong,
in my ears.
But now, after having both of them in front of me, at
the same time, I find myself accepting the name.
It is certainly a tube to go for.
(I can´t wait to I have the time to design an amp. with it.)
Halfin in Belgium, and James Whitehouse in Denmark are having
a stock of them. (I do not know their exact prices)
Michael Wiams at Halfin has told me that they sell a lot to
the Japaneese !
I am also pretty sure that Ned Carlsson, can manage to supply
you with 2E22, if needed.(Am I right, Ned ?)
Anyway, compared to the the KT66,KT77,KT88,6L6 , etc.
- the 2E22 seems a better choice, and at a fraction
of the price, charged for these beam´s.........
- sincerely Kurt Steffensen
Bob Miller
For what it is worth, the 2E22 was developed as a small transmitting
tube pentode where suppresser grid Amplitude Modulation was the economic
driving force ( I would speculate that the tube was designed in the late
1930s). The early WWII TBY transmitter/receiver was the first
Military radio I can recollect using the 2E22 with the late WWII BC-1306
single band HF transmitter/receiver being the second that comes to
mind. The later Korean conflict field radio, AN/GRC-9, a three band
variant of the BC-1306, that was probably deployed at the end of WWII
also used the 2E22 as its suppresser grid modulated Class C final
amplifier. I believe the French, in their early Nato days, fielded a
linear amplifier for the AN/GRC-9 using an array of 2E22s which may
explain the stock of European tubes turning up.
I cannot speak to the 2E22 as a hi fi amplifier device, but as an
"instant heat" directly heated fil tube for casual RF service they are
not too bad. I hope the HI FI tube dudes don't drive the prices of
these rascals out of site, but I'd be interested in what folks have done
with them in tube audio amps none the less.
Tnx for the read
Bob, KE6F
electro...@gmail.com
> Gent´s.
