Introduction

            Radio restorations come in many different flavors from the “get it done quickly” method of cutting and blob soldering components in place to the “conscientious method” whereby every effort is made to replicate the look of the original components.  In this particular restoration, I’ve opted for a middle of the road approach.  By this I mean that I replaced the wiring with the same color as found in the radio, although it is not cloth covered like the original.  The capacitors and dog bone resistors were also replaced with modern components with no attention to recasting them with the original labels.  In this restoration, I did pay particular attention to the dial face and label artwork as these items were very important in identifying the radio model number.

What I hope to communicate is to give the casual reader some insight into the work involved in a restoration process. The experienced repairman will undoubtedly appreciate the before and after pictures.

The radio was complete but in a very grungy condition. As you can see, the cabinet had several rub marks near the dials and the grill cloth was tobacco stained and dirty. When I inspected the back of the radio, there were more surprises as the chassis was badly rusted and the power cord showed signs of a current overload. Immediately I anticipated a blown transformer and my wallet began to ache as this component is rather costly to replace.

Next, I removed the chassis from the case and inspected what was in store for me. Fortunately, things didn’t look too bad as the wiring harness inside wasn’t burnt. As you can see however, I had my work cut out for me in this restoration.

No way would gentle sanding clean up this chassis. The first order of business was to remove the tubes and the gang tuning capacitor and take the chassis to the sandblaster. It is amazing what grains of sand under high pressure can do to a rusty old radio.

In this photo, I’ve already removed, tested, cleaned, painted, and remounted the transformer. The coils, tubes, grommets, and tuning capacitors have been removed. Most of the rub marks that you see are Dremel tool marks where I had to grind on troublesome spots. Next I lightly coated the chassis with WD40.

I attempted to faithfully follow the color scheme of the schematic in rewiring the radio. Most all of the radio used 20 AWG wire except for the coils.

Look at these before and after photos and notice how much smaller today’s electrolytic capacitors are. Scan over the left side of the before restoration photo, you’ll see the technician didn’t even bother to remove the old electrolytic capacitor. He just cut the leads and installed another component. (The bright orange device was one of the replacement capacitors.) See the tubular components painted with colored dots? If an old timer tells you that’s a dog bone resistor, he’s telling you the truth.

I’ve added two safety features to this radio during the restoration. First, I fused the hot side of the input with a 2A slo-blow fuse. Second, I added a "bucking" transformer (Radio Shack part #273-1352) to the input circuitry to reduce the input voltage from 124VAC to about 116VAC. This input voltage reduction is important because most radios manufactured in the 20s and 30s were designed for 110 to 116VAC inputs. With the higher input voltage in today’s households, the output plate voltage may come close to the maximum value rated for the tubes. This is hard on the components and reduces their lifetime.

I strongly felt that the documented history of a radio is important, so I enlisted the help of my cousin to assist with the artwork. She scanned the original into an application and edited out the smudge on the original label.

What you see in the reconstructed artwork is a label that looks much like it would in 1939. The same procedure was used for the radio dial face. After I printed the artwork, I pasted the dial face on some heavy paper similar to what is used to make boarders for pictures.

In addition to the stripping and finishing of the cabinet, the radio was in need of an alignment due to the extensive rebuild. I’m fortunate to have some high quality equipment to help with the job. Last year, I purchased an HP 8640B signal generator and a Fluke 177 multimeter from Tucker Electronics. These instruments have served me well in radio repair.

Take a look and enjoy a radio that is more than 65 years old. The unique green tuning eye gives a visual indication that a radio station is in tune. The stronger the signal, the more the green "eye" closes. This tuning eye option on some radio models was popular from about 1936 until the beginning of WWII.