FULL WAVE HIGH VOLTAGE RECTIFIER
G.E. and Amperex Available
The 8020 Vacuum tube is used in Radar equipment. It is
also used in electrostatic precipitator ( ESP ) machines.
Electrostatic precipitators ( ESP's )are devices that
remove suspended dust particles from a gas or exhaust by
applying a high-voltage electrostatic charge and
collecting the particles on charged plates.
This type tube is excellent for High Voltage line testing.
THIS INFORMATION WAS FOUND ON THE INTERNET:
Capable of handling voltages of up to 40 kV, this tube is
a real high-voltage rectifier. And it can handle
considerable currents, too: up to 100 mA, peak current
being much higher - about 1 A (the resulting peak power
being 40,000 Watts!). Needless to say, that at these
extreme voltages, it needs a perfect high vacuum for
sufficient internal insulation without the slightest
traces of gas. So, the cathode is a simple direct
heated pure tungsten filament rated at 5 V, 6.5 A. The
plate is made of a hard-metal with external
high-temperature getter coating (the grey center region),
like in transmitting tubes.
Some cooling of the top anode cap should be recommended,
since this tube has a quite high voltage drop of a few
hundred Volts. And with maximum current, a considerable
plate dissipation will be released - up to 100 Watts.
All pure-tungsten filaments should be heated only as much
as is needed to reach sufficient emission (contrary to
all other cathode types, especially thoriated ones, which
are the most sensitive to over- and underheating). Even
reduction of heater voltage by a few percent will
increase tube (filament) life two- or threefold.
As with all tubes operating at voltages above 10-15 kV,
considerable amounts of X-radiation might be emitted - in
rectifier tubes short pulses just at the moments as the
tube passes from conducting into cutoff state and the
high reverse tension starts to build up between cathode
and anode, and during cutoff state at maximum voltage
due to field emission effects.
So if you're experimenting with such devices - be careful
and take appropriate shielding measures! Needless to say
. . . . .
These High Tensions are ABSOLUTELY LETHAL ! ! !
So do me a favor and be Careful. I have a hard time
selling to repeat customers who keep dieing on me.
Smile! ~ Rod
CROSS REFERENCE ......................451 and 578