Re: Unknown tube

Fivre is probably the name of the manufacturer. You've found a fairly
obscure tube, but I did find a data sheet for the 4C35, which is
probably a lower-powered version.

The 4C35 is a hydrogen-filled thyratron tube, designed as a high-speed
switch. The hydrogen allows an extremely high plate voltage (8 kV
maximum forward peak, 2.5 kV maximum reverse peak) and high pulse
current (90 amps maximum peak, 100 mA maximum average). Its heater takes
6.3V at 6.1A. There's no basing listed, so you're on your own there. To
make sure we're talking about roughly the same tube, the external
dimensions are 7" high and 2.5625" diameter. It should be fairly good
for Tesla service, as long as you're not planning to put out too much
power (.8 kVA max). Also, it looks like you may need to have a source of
hydrogen, since one of its equivalent tube types is listed as having an
integrated hydrogen source. I would think that the gas would deionize on
its own, but I'm not really sure.

Hope this helps!

Tesla List wrote:

> Original Poster: Mazzilli Vladimiro <mazvla-at-iol.it>
> Hello all,
> Can anyone help me to have the principal specifications of the tube
> FIVRE 4C100T
> Thank a lot
> Vladi.