Category: Volume 21

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Volume 21 - No. 5

Vol. 21, No. 5

On the Cover The “Voltage Amplifier Tube – Huth” with a clip-in ballast resistor matched to its filament drain, from the Dr. Erich F. Huth Gesselschaft just after WW1. In this issue

Volume 21 - No. 6

Vol. 21, No. 6

On the Cover The Telefunken 201, a field-effect device using a sprayed-zinc coating as the control electrodet. In this issue