Henry Kolesnik wrote:
I got a couple of the subject tubes which are supposed to be "glow
modulator tubes". Best I can determine is that the light output will
vary with current but I can't find data sheet googling. If anyone has
pinout and/or data I'd sure like to see it. I think it might be a mid
1960s item as my 1957 Sylvania manual doesn't show it.
thanks

Sounds like what we used to call "crater" (sp?) tubes and were used in
NOAA weather satellite optical printers for APT data in the 80's.
Muirhead (UK) was the mfgr. of the receiver/printer units. I simply
don't recall who mfg the tubes, though. They were octal based, however.