Detrola Model 105C 5-Tube Dual-Band A.C.-D.C. Superheterodyne
November 1936 Radio-Craft

November 1936 Radio-Craft

November 1936 Radio Craft Cover - RF Cafe[Table of Contents]

Wax nostalgic about and learn from the history of early electronics. See articles from Radio-Craft, published 1929 - 1953. All copyrights are hereby acknowledged.

Detrola Model 105C (RadioMuseum.org) - RF CafeI have been scanning and posting Radio Service Data Sheets like this one featuring the Detrola Model 105C 5-Tube Dual-Band A.C.-D.C. Superheterodyne radio receiver for many years now. There are still many people who restore and service these vintage radios, and often it can be difficult or impossible to find schematics and/or tuning information. The thumbnail image of the Detrola Model 105C radio is from the RadioMuseum.org website.

Detrola Model 105C 5-Tube Dual-Band A.C.-D.C. Superheterodyne

Detrola Model 105C 5-Tube Dual-Band A.C.-D.C. Superheterodyne, November 1936 Radio-Craft - RF CafeThe high-voltage D.C. in this receiver is 120 V. from "B+" to "B-," and 105 V. from "B+" to chassis, the difference of 15 V. being the drop in the filter choke that is applied to the C.G. of V 4. These voltage values hold true with a line voltage of 115 V. Alignment procedure is as follows: Align the 1st and 2nd L.F. transformers to 370 kc., with the output from the signal generator connected between the grid cap of V1 and the chassis. Then connect generator to antenna and adjust wave trap, located on right-front of chassis, to point of minimum re-ceiver output with 370·kc. input. Open receiver gang condenser to minimum capacity and adjust the receiver to 1,650 kc, with the rear trimmer on the gang condenser. Tune in 1,400-kc. signal and adjust front trimmer on gang condensers to maximum. Tune in 600-kc. signal and while rocking condenser slightly back and forth, adjust padder located on top of chassis between variable condenser and speaker, to best response. Repeat alignment at 1,650 and 1,400 kc.

 

 

Posted January 20, 2017


Radio Service Data Sheets

These schematics, tuning instructions, and other data are reproduced from my collection of vintage radio and electronics magazines. As back in the era, similar schematic and service info was available for purchase from sources such as SAMS Photofacts, but these printings were a no-cost bonus for readers. There are 227 Radio Service Data Sheets as of December 28, 2020.