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The Cabinet.
Click here for pictures.
The cabinet is in poor condition, and will have to be refinished. Refinishing
of the cabinet is complete
The Chassis.
Click here for pictures.
There is only one chassis in the set, and it is identical to the TT-5
chassis. This chassis is in good condition, and is mostly complete.
Click here for technical information.
The chassis will be cleaned with water and a mild detergent using
soft brushes to get into small places. Then, all paper capacitors
will be replaced with modern ones (see the procedure
for this). Each electrolytic capacitor will be tested for leakage and
capacity. If bad, new electrolytics will be installed
inside the old ones. The high voltage (EHT) capacitor also had
to be rebuilt.
The chassis in this set appears to be a prototype. The channel
selector shaft is only partially milled, and the fine tuning
capacitor has been removed, perhaps to make room for the experimental
placing of the shield. There is no serial number stamped on the
chassis, and the soldering is less professional than is typical of
these sets. Also, the video amplifier tube socket is wired for a 6AC7
or 6AG7. Did RCA originally plan to use that tube, and then decided
on the 6V6?
There are several pencil marks to mark the place where holes are to
be drilled. These mark the location of holes for the metal shield
behind the tuner:

There is an extra hole punched out for an IF transformer which
was not used in the production chassis:

There is also this marking on the side:

The power transformer is defective, and can't be rewound. I've had a
replica made, which is similar, but not identical, in size. I will
attach the original transformer covers to the new transformer and
then paint the assembly black.

The completed transformer, mounted on the chassis

We now have the power supplies and sweep sections working. We are now
trying to get the local oscillator to function. It appears to be
wired properly, and all the parts check OK, but it doesn't work.
A bad ceramic capacitor was found, and the local oscillator, IF, and
audio sections now work. The next step is to replicate the missing
fine tuning trimmer and shaft.
We have made a replica of the original fine tuning assembly. First, a
variable capacitor was found that was similar to the original.

All but two of the stator plates and one of the rotor plates were
removed. Then, a new bracket was made of aluminum. A 1/8 inch brass
shaft was soldered to the end of the capacitor, and the joint was
covered with heat shrink.
The assembly was installed on the original tuner. The brass rod goes
inside the channel selector shaft and extends out the front of the
chassis. A piece of 1/4 inch brass stock was cut off, drilled for the
1/8 inch rod, and filed flat to match the fine tuning knob.

Restoration of this set is now complete.
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