Nick wrote: ↑Tue Feb 27, 2024 11:09 pm
What an interesting valve. A one socket push pull output stage.
I've got 10 of those, NIB. They were for a project that, like many others, I've not yet found the time for. At one time I had a thing for "spud" amps, so these made sense. E = 6.3V, C = Triode, LL = 2 x Output Pentodes, 8 = B9A base
They are a true compound tube from around 1964, approximately equal to 1/2 x ECC83 and 2 x EL95s in a single envelope . Mine are made by ITT/Lorenz. Lots out there about them, including in this fascinating copy of Practical Wireless from March 1964:
https://worldradiohistory.com/UK/Practi ... 964-03.pdf
If you like compound tubes, there's also a few 6M11s which are 2 x high mu triodes and a sharp cutoff pentode, similar to a pair of 12AT7s and a 6EW6 in a single compactron envelope. Again, there are some spud projects around these, e.g.
https://www.diyaudio.com/community/thre ... mp.245813/
Also have some Mullard-designed PCL86s, which are 1/2 an ECC83 double triode and an EL84 pentode, again in a single envelope. These were intended for good quality TV output stages. They're cheap and plentiful (like most TV tubes).
Morgan Jones wrote: ↑Tue Feb 27, 2024 10:55 pm
All interesting stuff, and I'm sure there will be people there keen to take them off your hands. I might have to take a look at your EL84. Don't think I've even seen an ECLL800.
There's 2 matched pairs of EL84s - don't know the makes offhand - I'll have to dig them out.
I'll bring some ECLL800s for show-n-tell! If you want one to play with, I'm sure we can do a deal.
The sub miniature tubes, aka "rocket tubes", are extraordinary devices that I have in quantity - 100s of most types (original US military bulk boxes).
I do have some decent fans...