OT: white LEDs

[Tony Duell]

> In the US, there was the All-American Five design that was used by nearly 

Sure. IIRC there were several versions with octal, single-ended octal (no 
top caps), all-glass miniatures, etc. Wasn't there even a Loctal version?

> all manufacturers for the lower end models.  The heaters were wired in 
> series and the voltage drop added up to 121.  That was close enough for 
> 120VAC and thus the transformer could be omitted.

And no dropping resistor either. I seem to remember valves like 12K8 
(changer), 12K7 (IF amplifier), 12Q7 (detector/audio amplifier), 50L6 
(output) and 35W4 (rectifier). 

We did get those sets occasionally in the UK. They were fitted with one 
ofd those 'line cord' dropping resistors to allow them to be used on 240V 
mains.

-tony