Sparton Radios



Again, I want to apologize for the poor quality of these pictures. I will upload better ones as I have time to take them with my digital camera.
Sparton was the brand name for the Sparks-Withington Company of Jackson, Michigan. It started out in the year 1900 making small stamped metal parts and soon was making parts for the growing automobile industry. In 1925, they started making radios and became a big radio manufacturer in the 1930s. They later branched into Televisions after the war, but stopped making radios and televisions in 1958. They changed the name from Sparks-Withington Company to Sparton Electronics in 1956 and are still in buisness designing, engineering and manufaturing for the aero-space and medical fields. They can be found at http://www.sparton.com of course.
One of the main reasons I'm interested in Sparton is that they were the biggest company to use the "Technidyne" circuit.
Read more about this amazing circuit here.

The Technidyne


Read about my collection of some of the best radios Sparton made during the 1930s. The Triolian Series.

The Sparton Triolian Project


The Sparks Ensemble model 99 (1928)




Again, I'm starting off with a bang as this is the physically largest Sparton radio in my collection. This is the Sparton equivelent to the Zenith model 40A. It is another massive set as it took four people to move it. This radio uses the unusual "Technidyne" circuit invented by Lester Jones. It was a way to get around being licensed by RCA.
It is a unique circuit as all the tuning is done first, through a 4 stage tuner, then the signal is amplified with a broad band untuned self-neutralizing 5 stage RF amplifier. It is quite amazing this circuit works at all, but it does, and very well!

It also has a record changer which is a mechanical marvel! The records hang above the turntable from a large "Elephant Trunk" shaped assembly, the turntable spindle lifts out of the turntable and trips a lever on the mechanism holding the records and releases one record. The record is lowered onto the turntable where the tone arm moves over and plays the record.
When the song is finished, there is a rubber bumper which lifts the back edge of the record causing the turntable to "Fling" the record into a shute and down into a padded drawer in the center of the cabinet. Then the spindle lifts up for another record.

Needless to say, many records were broken or badly scratched by this "contraption"!

The radio uses 11 tubes in 4 seperate chassis. It uses six type 484/485 Sparton (Cardon) tubes in the RF amplifier, one in the phono amplifier chassis and a pair of type 50s with a pair of 81s in the powersupply/audio amplifier chassis. Unfortunatly, those 50s are getting hard to find...

The speaker is an 8 inch Magnavox with the old "Chamois" surround. this usually rots and crumbles and needs replaced not unlike the foam surround of many modern speakers. This radio is partially restored, but the phono pickup needs repair. As I have time (Haha) I will finish this set.

More to come