6E5S, 6E5C Russian Tuning-Eye Tubes

An update:
I gave the Soviet 6E5S tubes (6V heaters & octal based) a try in one of my Eico 950A capacitor checkers. It was easy to get it working but if you want to try any of these tubes keep in mind the fact that the manufacturers used rather thick bases on the glass tubes so they won't fit easily into the usual clamp type eye tube holders. Also, stick to buying "new" unused tubes only as the used ones I bought, while "tested and working", were not bright enough to use.
73, Rod  WB6FBF

The 1629 eye tube needs 12 volts on the filament, so you would have to use a voltage doubler.
     I do not know if there are  other changes you might have to do.
 Dan in Calgary.

I am looking into buying some of the Russian/Eastern Europe made 6E5S tubes to try as a replacement for 1629 tubes in the various vintage capacitor checkers. Anyone have experience using these tubes? I think they might work with just a jumper at the tube socket from pin 4 to pin 6 and a slight rearrangement of the filament circuit. Any thoughts?
73, Rod  N4QNX