The gamma 10 has two control panels: a technical one behind a door, and a small one sticking out of the machine.
Both control panels have glowing indicators that are actually built out of vacuum tubes. The tubes are small indicator tubes with DM160, that have a heater voltage of 1 V and are operated at an anode voltage of 45 V. The grid of the tube is connected to the logic circuits, allowing readout of the binary state without loading the circuits.
