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Model 70 Schematic
#1

Having  problems  with a Model  70 (early) finding a schematic that identifies the value of those molded caps. Specificly Part # 4989C, 4989E, 3903L. The tube layout (single 47 output) says this is an early model but the serial number is 726678 - way over the 22000 that the Rider Manual lists for the early production.
#2

Hi and welcome to the Phorum,
Perhaps this will help  https://philcoradio.com/library/images/schem/70a.jpg To be honest I rarely use the Philco part numbers to determine the part values I just use the under the chassis placement drawing and number. Then double check it's wiring against the schematic.  The model 70 in all of it different alliterations only used a single 47 tube for it's audio output. Early and late model 70's are strikingly different electronically as the early doesn't have an avc circuit (note the dual volume control) vs the late which does and has a single control. Would get too bogged down the serial numbers.

GL on your new adventure!

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

THANKS!  Finally a schematic with some values for the caps & resistors.
#4

If you still want those values I could look in my Ray Bintliff book, it likely has them. That will have to be this evening.
Let me know.

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.
#5

Welcome to the Phorum!
Icon_wave

The Philco Library has a lot of information that folks sometimes don't see....check it out...(all part of Philcoradio.com)
https://philcoradio.com/library/




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