Eusebius wrote:

Yes, by definition, if it used the European numbering system and began
with D, it was 1.4v for the filament/heater. Designed to run off dry
cells (I had a radio with those for years...a portable too!).

The valves are 26 - american type, and yes each is 1.5v at 1 amp. Not
the usual radio valves, which were more like 0.1 Amp. You could use D
cells for those. And yes, the European valves were often 1.4v like 3A5,
1LE3, DC90, DC93, DC96. DC96 had only 30mA of filament current.
The CPC link was absolutely right - probably the lowest prices. Looked
them up in my catalogue, then phoned the supplier. Cyclons (2v) should
be charged at 2.35v, and can be done so in a single stage - just needs
a very smooth supply of about 1% ripple and capable of 2 amps according
to them. Sounds like a DIY power supply would do this.


I dont have a direct answer, but a few thoughts...

1A heater current is huge for filament valves: are these indirect
heated valves by any chance? If so, you can put muck through them quite
happily. A chopper to deliver the 6v at 1/16th duty cycle would work.
No way could you do that with direct heated filaments of course.

Any lead acid can be converted to gel cell by mixing the right stuff
into the electrolyte and pouring it back in. Trying to think, sodium
silicate?

Finally your local lead acid battery manufacturer could always provide
a cell to order.


NT