Please scroll down for the photos

 

 

The pictures in this sub directory are the final modifications
that were made to the original design of the receiver as published
in the January, 1937 Popular Mechanics Magazine.

The earlier photographs were of the first working version. The receiver
would only tune the AM band. The reason for this was lack of the
coils specified in the construction article. These coils haven't been
available for a number of years. I had to experiment with the AM broadcast
coils to get the right turns to allow the oscillator and input RF coils to track
properly. To add the short wave bands, it would have taken a lot of effort.

I went to the California Historical Radio Society's Swapmeet in Concord, CA
in March, 2005. I was seeking amongst other things, a set of RF and Oscillator
coils that could be put in this project.

I spotted a Silvertone table model receiver that was in very poor condition. The
case was falling apart and it was very dirty inside. It had BC and SW bands on it
and a very nice art deco dial and bezel. It was exactly what I was looking for. I
purchased the receiver for $15 and took it home.

The model # of the receiver was 101.487. It was made in 1937. It was the exactly the
right era.

The receiver was apparently stored in a moist area since the plywood was de-laminating.
It also had mud dauber nests inside as well. The coil and band switch assembly was
easily removable as a unit. The tuning capacitor, bezel, and art deco dial was also
removable. The receiver parts that were removed were filthy and had to be scrubbed
with Simple Green. Then they had to be washed with clean water and flushed with
alcohol to remove the excess moisture and dried. Except for the items removed the
rest of the receiver was junk except for the tubes and tube shields. One of the form
fitting tube shields is used in my receiver.

The previous tuning assembly was removed and the new tuning assembly was
transplanted into my receiver. After some wiring errors were resolved, the receiver
was aligned.

The results are spectacular. The new tuning assembly has a double tuned input coil
that eliminates image response on the BC band. The first configuration did have
some images show up from strong stations at the top of the BC band. The
short wave bands are also spectacular. The receiver covers from 3.5 Mhz to 12.5 Mhz.
When the antenna is connected to a good outside antenna like a 40 foot sloper,
it is like tuning the BC band with all the short wave stations that it picks up. I connected
a signal generator loosely to the IF stage at 455Khz to make a beat frequency oscillator
and was able to pick up single sideband stations on 75 and 40 meters.

The receiver exceeded my expectations, both in sensitivity and audio fidelity.

An Art Deco cabinet was constructed using hemlock and poplar wood to complete the receiver.

I have reached my goal of a "new" 1937 receiver. (my birth year)