CAR RADIOS RESTORED TO FACTORY SPECIFICATIONS
1957
...HONEYCOMB... THAT'LL BE THE DAY... MR. LEE... BLACK SLACKS...
...WAKE UP LITTLE SUZY...REET PETITE...THE STROLL...
...USSR puts sputnik in orbit, launches another with dog Laika...
Here's the radio from Cars & Parts
Magazine's project car "Peggy Sue". A 1957 Chevrolet convertible.
Looks pretty rough, huh? Well stick around and watch the transformation from
nasty to nice.
This radio, model # 987575 is the first factory radio to employ a transistor
rather than the usual vibrator-transformer-rectifier type power supply. Known as
a "hybrid" it used new tubes that got their power directly from the 12
volt battery. It also featured a printed circuit, quite an innovation 47 years
ago. 
The first thing we'll do is
disassemble the radio into it's various sub-assemblies. This series of radio was
one of the first to use unitized construction. Some of the parts were mounted
directly to the case. The transformers, filter capacitor etc. are removed and
set aside. The main chassis is disassembled far enough for cleaning.
The outside case pieces and hardware is then glass beaded and cadmium plated.
The printed board and tuning assembly is ultrasonically cleaned. The dial
background and frame is cleaned and repainted. The faceplate and bezels are sent
out for chrome. Now we get to the electronics. First, we'll replace all
the paper and electrolytic capacitors. Clean the tube sockets and check the
condition of the wiring. In these radios, the 10 ohm resistor for transistor
bias is usually out of tolerance so it will be replaced. If everything checks so
far, the sub-assemblies will be put together. The radio will be reassembled far
enough to allow testing and alignment. 
All mechanical parts have already cleaned and degreased, so lubrication is
necessary. Here, I'm cleaning the tuner clutch. The tuner will then be checked
and adjusted for zero backlash etc. It should operate smoothly with no binding
and the pushbuttons should accurately set the tuner to the station they are set
to. New plastic buttons are installed at this time
The radio will now be tested for power output,frequency response, distortion
sensitivity, selectivity and drift. If it passes all these tests, it will be
test run for 30-40 hours for long term stability. Once it gets through that
perfectly, all the restored cosmetic parts are put back on along with new wiring
for the dial lamp, "A" lead etc.
...LITTLE BITTY PRETTY ONE...AT THE HOP...GREAT BALLS OF FIRE...
...OH, BOY...SUGARTIME...26 MILES...FOUR WALLS...
...Oscars to Yul Brenner (The King and I)...Ingrid Bergman (Anastasia)...
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