Howard Model G-26, and "Airplane 4" Model AA25 A.C.-D.C. and Battery T.R.F. Set Radio Service Data Sheet
January 1936 Radio-Craft

November 1935 Radio-Craft

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

Howard Model G-26, and "Airplane 4" Model AA25 A.C.-D.C. and Battery T.R.F. Set

Four of the newest-type glass tubes are used in this compact set. The T.R.F. circuit is designed for the utmost gain from the tubes available, and is very efficient. The airplane-type dial (model AA25 set) in-cludes two standard pilot lamps, across which is wired a limiting resistor. (Placing the tuning dial directly in the center of the reproducer tends to improve tone quality by reducing the amount of highs in the reproduction.)

The airplane dial of this set changes illumination as the bands are shifted. Both halves are lighted on the broadcast band the upper half on the S.-W. band, and the lower half on the police band. The tuning ratio is 60-to-1 on the high position. The selectivity control makes possible true high-fidelity when in the low selectivity position. In addition, a 4-position tone control is used. Correct tuning is shown. by observing the shadow tuning meter, which is operated by the plate current of V2 and V3. The set draws 120 W. from the line. The range switch has 3 sections, each of which changes 3 separate circuits.

Posted December 14, 2016

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.


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Howard Model G-26, and "Airplane 4" Model AA25 A.C.-D.C. and Battery T.R.F. Set Radio Service Data SheetJanuary 1936 Radio-Craft

Howard Model G-26, and "Airplane 4" Model AA25 A.C.-D.C. and Battery T.R.F. Set Radio Service Data Sheet
January 1936 Radio-Craft