How Philips made RF & IF transformers 1937/48 ? (Algemeen)

door John Hupse † , Schoonhoven, 21.08.2015, 19:03 (3384 dagen geleden) @ Robert Lozier

this picture published by Ger Fust shows how it was done. The rill into the aluminium shielding of the coil can be made deeper by moving the handwheel at the left side. A r.f. signal generator (left side of the control panel) is used to feed the coil assembly with a signal. At the same time the output voltage of the coil assembly (coil inductance, fixed capacitor and a compensating capacitor) is indicated on the voltmeter at the right side of the control panel. This way the operator is able to tune the coil assembly to the correct frequency.

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