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Philco 38-2 Automatic Tuning
#3

When you push the lever, you are supposed to rotate the disk to the desired station.
Then the magnetic tuning will acquire the station and lock to it.

It is a form of AFC (auto freq. ctl).
I works as PLL (Phase locked loop), where the two wfrequencies are compared, the difference is converted by the discriminator into the positive or negative pulses, which then are smoothed (integrated) by a filter (a capacitor), and the voltage developed on this capacitor controls the frequency of the VCO (a Voltage controlled oscillator), which intern compensates for the station frequency deviation, or, if needed, for the inaccuracy of the positioning of the tuning cap (as this mechanism has an error).

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Philco 38-2 Automatic Tuning - by dconant - 11-03-2024, 11:51 AM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-03-2024, 01:11 PM
RE: Philco 38-2 Automatic Tuning - by morzh - 11-03-2024, 02:42 PM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-04-2024, 08:22 AM
RE: Philco 38-2 Automatic Tuning - by radiorich - 11-04-2024, 09:14 AM
RE: Philco 38-2 Automatic Tuning - by morzh - 11-04-2024, 10:50 AM
RE: Philco 38-2 Automatic Tuning - by RodB - 11-04-2024, 11:00 AM
RE: Philco 38-2 Automatic Tuning - by morzh - 11-04-2024, 11:55 AM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-04-2024, 01:17 PM
RE: Philco 38-2 Automatic Tuning - by morzh - 11-04-2024, 03:20 PM
RE: Philco 38-2 Automatic Tuning - by radiorich - 11-04-2024, 03:56 PM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-04-2024, 04:13 PM
RE: Philco 38-2 Automatic Tuning - by rfeenstra - 11-05-2024, 01:20 AM
RE: Philco 38-2 Automatic Tuning - by poulsbobill - 11-05-2024, 12:16 PM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-05-2024, 06:45 PM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-11-2024, 12:39 PM
462ron - by 462ron - 11-12-2024, 08:58 AM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-12-2024, 09:23 AM
462ron - by 462ron - 11-12-2024, 09:40 AM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-12-2024, 09:51 AM
462ron - by 462ron - 11-12-2024, 10:34 AM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-21-2024, 11:13 AM
462ron - by 462ron - 11-21-2024, 12:07 PM
RE: Philco 38-2 Automatic Tuning - by dconant - 11-21-2024, 12:27 PM
RE: Philco 38-2 Automatic Tuning - by morzh - 11-21-2024, 08:11 PM



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