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Oct 11 2014

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GU-81 by night …

P1120066 b

These are some preliminary shots of a GU 81 tube, after it is heated up – just a tiny little bit.

Actually, the heater requires 12,6V with a current of 11 A.

I used a 12,5 V AC toroid, rated at 150 W, but unfortunately, the toroid that I used, under the load, …  sort of … started sagging, so it gave no more than 11,7 V …

Therefore, it would be fair to say … that the tube is grossly underheated …

P1120072 b P1120075 b P1120077 b P1120054 b P1120056 b P1120057 b P1120059 b P1120060 b P1120062 b P1120063 b P1120076 b P1120078 b P1120055 b P1120058 b P1120064 b P1120065 b P1120068 b P1120069 b P1120070 b P1120073 b P1120074 b

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