Photo electron tube mic prepreamp

Electrons can be emitted by light, photons striking the cathode.


The few megohms electron accelerating resistor from anode to grid makes operation possible with just a few volts at the anode. The electron tube operates successfully with a low (in micro amps) current at very low noise.


Is this suitable for space supplications?


Notes


Same as Pleiades V6 preamolifier.


But electrons are emitted by light striking  on cathode.


Same idea anode to grid few Megohm resistor as electron accelerator.


Would this be useful in satellites, radio telescope, space communication?


Reference:


Pleiades V6 schematic


Neumann U47 schematic


On preserving transconductance - Euroelectron blogspot