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Philco 38-7XX wafer switch positions?
#1

Hello -

I am re-doing a 38-7XX chassis for a friend and I have a question:

The middle knob is a wafer switch with three positions. The middle position is AM and the rightmost position is shortwave There is also a left position which seems to do nothing at all.

My question is:

What is the leftmost wafer switch position normally used for? Muting? Some sort of phono input?

Thanks!

Matt
#2

I took a quick look at the diagram and there is an audio mute position on the band switch. Generally speaking it would be odd to find a set with an audio input as they where marketing their our phono oscillator to broadcast to their sets.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

The audio mute is for the Cone-Centric automatic tuning mechanism. When a station is being tuned in with this mechanism, it is supposed to mute the audio until the tuning knob is released (pulled back away from the cone). This has nothing to do with the band switch.

The band switch is only a two position switch since the set has but two bands (the AM band, and shortwave from 5.7 to 18.2 mc). Either yours is broken, or has been tampered with.

Oh, and Philco did not start marketing their wireless phonographs with the built-in phono oscillators until the following year. Icon_smile

--
Ron Ramirez
Ferdinand IN
#4

Oops Sorry for the wrong answer. Sounds like it's set up like the mute for the magnetic tuning set of 1937.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry




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