|
The
resurrection of a dinosaur
Templetone Radio Console from 1929
This handsome beast was to be offered as-found but before my
photo-shoot I decided took a closer look for a better
description of it's condition. At first I was impressed with the
high quality construction and streamlined, clean chassis detail.
Featuring an exceptionally large (for it's time) electrodynamic speaker and impressive 4 tuned RF stages with push-pull 45's
for output tubes.
My thoughts while disassembling
this radio was that some of the designers of this and other
radios late 1920's behemoths must have been former WW-I
tank designers as as everything seemed to be made to withstand a
bomb blast.
Next I proceeded to remove the
chassis and look it over. It did not take long before I realized
that someone had been here before. In spite of it's, clean
unmolested appearance, one of the two
component cans had been gutted leaving all the wiring
dangling underneath the well shielded chassis with no diagram.
So I searched for a schematic with no success. Both Riders
and Official publications had one that was similar but
not the same. The next two - three hours were spent drawing up a
wiring diagram so I could determine what was in the large empty
can. The results were two audio interstate transformers, a
resistor and capacitor. I'm sure glad I did not offer this piece
as is for several reasons, not the least of which....having an
unsuspecting buyer getting more of a project than he bargained
for and the likelihood of creating some ill will. I was now
determined that this set should be heard before offing it for
sale.
It was now obvious that I was
going to have to do full electronic
restoration if I was to bring this monster back to
life.
The Next Step
Before getting too much deeper in
what now to be a several day project, I needed to make
sure all the special components such as the power transformer
and tuning condenser were ok. Fortunately the tuning condenser
was free of pot metal and
the power transformer with no load checked out great on all
windings. I did notice that the large umbilical cord (connecting
the main chassis to the power pack) had some brittle &
flaking of the rubber wiring insulation at the terminals on both
ends. The cable seemed flexible otherwise and nothing was
shorting or bare at the important spots so I decided to leave
the cable as is and handle it with care.
The Audio Transformer Can
New audio transformers were
installed inside the original can. I used the common 1:3
ratio interstage transformers that are readily available from those that cater to
the likes of guys like me. The terminal strip at the opening to
the chassis underside was missing, so new one had to be
fabricated.
The Capacitor Can
Right next to the audio can was
another can, identical in external appearance containing the
filtering and by-pass capacitors. I decided to gut and replace
them all. The method to remove the guts from such cans is tip
#10 on my Tech Tip Page.
As you can see in my
photos with the top of these two cans removed, the new
components only occupy a small fraction of the space the
original components did.
The Smoke test
After all the above was completed
plus re-stuffing of a smaller external capacitor pack and
replacing two other small components I was ready for the first
"play" test. The results left a lot to be desired, poor
selectivity with strong stations booming in and poor control
over the volume. Not too surprising as the signal and volume
control design of this set was typical to others of the times.
The volume control was very noisey and intermittent and cleaning
it did not help. Engineers of the early days had not yet discovered
AVC and none of
the usual methods of volume control were very good. Most were
quite simple, they just dealt with attenuating the antenna
signal at the first stage. The more sophisticated control had a
dual pot that increased in resistance on one section
while the other section deceased. This allowed the gain of the
antenna and RF stages to be controlled together. These were
special parts that are often defective and nearly impossible to
find or replace with something suitable of modern design. So
what to do???
Now What
Make some changes in the basic
circuitry! To some, this is heresy and I suppose if you were
dealing with an extremely rare piece I would agree. But radios
such as this are not rare and are not of high value to most
collectors even if they are working. So what I do with some of
these is to make a few minor modifications that I do not feel
does anything except increase the value to someone that wants to
use the radio for his listening pleasure. The modification I have done
to this radio makes it play like a million bucks and
uses all of the original circuitry. In fact, you will
have to look hard with a very technical eye to even tell that it
was modified. As I said, all the original parts are still in
place and used (with a couple of minor exceptions). The added parts are tiny,
they are hidden and they are
not transistors.
A hidden AVC circuit
Adding an
AVC circuit and a conventional volume control
to an early radio such as this one is a great improvement. For those
interested I can furnish the details and schematics to do so for
a modest fee. As for this set which now works and sounds great
has better sensitivity than many typical, popular modern
super-hets. I offer some images of the chassis before and after
modification. This modification can also be done on the Philco
90's and other radios that use that dual volume control.
How to do it
Here's a quick and simplified
approach to how I place
AVC in one
of these early sets. First some additional components are
installed in the present RF circuit stages (a small capacitor
and resistor). I prefer to hide them inside the
RF
transformer cans as can be seen in the
photo. The AVC detector circuit is all contained in the
small Mallory box as can be seen in the
after mod photo. For the purest who may want to put the
radio back to it's all original state, these components can
easily be removed and the radio put back to original. The
original dual volume control must be removed and a common type
be added in the audio stage as they are in a typical more modern
radio.
click on
images below to enlarge
 |
 |
 |
 |

rear view |

cabinet top |

power pack |

inspection tag |

chassis front |

chassis underside
pre-modification |

chassis underside
post-modification |

ID badge |
This is now a great performing radio, tunes all am stations
smoothly and clearly across the dial with great sound. The
original finish is not perfect but looks very presentable. The
case is sound, no moisture damage, has been kept in a clean
hospitable environment. I'm offering it with the antique globe
tubes as shown. These tubes alone would sell today for more than
$350.00.
Year: 1929
Cabinet: various wood veneers
Dial: lighted
Back: n/a
Finish: original
Knobs: original
Chassis: very clean
Tuning type: capacitance, TRF
Power transformer: yes
Grille cloth: original
No. of tubes: 9
Electronic condition: restored, excellent
Flaws, cracks, blems : typical wear, minor scuffs & blems,
worst on top
Frequency coverage: AM
Antenna requirements: long-wire
Measurements (approx): LARGE! 54 x 29 x 16"
Standing weight: HEAVY! - 120 lb
SOLD
return to previous page |