10-20-2016, 06:11 AM
Arran;
Thanks for that response. The schematic does seem to indicate that there is an adjustable ferrite slug present. It shows the adjustable trimmer capacitor on the secondary feeding the grid of the 1st IF amplifier tube. Your set appears to match the indicated circuit on this schematic.
I have a Philco 40-201 I restored and it is somewhat similar, in that it uses a broadly tuned RF amplifier (1232 pentode) followed by a 7J7 mixer-oscillator. The 1st IF transformer in it has two ferrite adjustable slugs plus a tertiary winding feeding the suppressor grid of the 7B7 1st IF amplifier tube. So my 40-201 has some significant differences, but similarities at the same time. It appears to be another design to incorporate higher selectivity in the IF circuitry. Philco began to use the broadly tuned RF amplifier on many models for a number of years.
Joe
Thanks for that response. The schematic does seem to indicate that there is an adjustable ferrite slug present. It shows the adjustable trimmer capacitor on the secondary feeding the grid of the 1st IF amplifier tube. Your set appears to match the indicated circuit on this schematic.
I have a Philco 40-201 I restored and it is somewhat similar, in that it uses a broadly tuned RF amplifier (1232 pentode) followed by a 7J7 mixer-oscillator. The 1st IF transformer in it has two ferrite adjustable slugs plus a tertiary winding feeding the suppressor grid of the 7B7 1st IF amplifier tube. So my 40-201 has some significant differences, but similarities at the same time. It appears to be another design to incorporate higher selectivity in the IF circuitry. Philco began to use the broadly tuned RF amplifier on many models for a number of years.
Joe
