by EWBrown » Tue Apr 07, 2015 6:15 pm
This Is a posting about this very subject, I made back in December 2013:
For what it is worth, 12B4As can be used in the Clementine / Darling circuit, with no resistor value changes.
12B4A is a noval 9 pin miniature, so it cannot just be plugged directly into an existing Clem.
With 250VDC B+ and 1K cathode resistor, it also draws 25 to 27 mA, with a 5K OPT, it delivers 1.5W rms.
It would not be difficult to wire up a pair of octal to 9 pin adapters, in order to make 12B4As work in the octal sockets.
One of my near-future projects will be to add the two 9 pin tube sockets to an existing Clementine,
or point to point Darling, and wire them up pin parallel with the 1626, and make it be convertible for either tube type.
/ed B
Real Radios Glow in the Dark
The 1626s will produce about 750 mW per channel, the 12B4As, 1.5WPC.
Last edited by
EWBrown on Mon Apr 13, 2015 11:59 am, edited 1 time in total.
Real Radios Glow in the Dark