Crosley Model 425 (Travo) 4-Tube Portable A.C.-D.C. Superhet
Radio Service Data Sheet
March 1936 Radio-Craft

March 1936 Radio-Craft

[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.

Crosley Model 425 (166?) "Travo" RadioMuseum.org

This Radio Service Data Sheet is for the Crosley Model 425 (Travo) 4-Tube Portable AC/DC Superheterodyne radio which appeared in the March 1936 edition of Radio-Craft magazine. No example of this 1935-era Crosley Model 425 could be found in searches, but interestingly, the term "Travo" returns a Model 166 by that name and the same year of manufacture. I post this schematic and functional description of the manufacturers' publications for the benefit of hobbyists and archivists who might be searching for such information, either in a effort to restore a radio to working condition, or to collect archival information.

Crosley Model 425 (Travo) 4-Tube Portable A.C.-D.C. Superhet Radio Service Data Sheet

(Pilot light; dynamic speaker; antenna attached; 6-tube performance)

This 4-tube set uses 2 double-purpose tubes so that the performance is equivalent to a 6-tube outfit. The 25Z5 rectifier is used in a half-wave circuit.

The antenna is of the type ordinarily used in A.C.-D.C. sets; that is, it is attached to the set and is uncoiled when needed. No ground is necessary. The circuit is insulated from the chassis so that no accidental shorts can take place.

Note that the pilot lamp has a resistor across it to limit the current flow.

Posted September 22, 2022
(updated from original post on 7/13/2015)

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 255 Radio Service Data Sheets as of April 30, 2025.

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website: AirplanesAndRockets.com

My Daughter's Website: EquineKingdom

Crane Aerospace & Electronics (RF & Microwave) - RF Cafe

Innovative Power Products (IPP) Directional Couplers - RF Cafe

Crosley Model 425 (Travo) 4-Tube Portable A.C.-D.C. SuperhetRadio Service Data SheetMarch 1936 Radio-Craft

Crosley Model 425 (Travo) 4-Tube Portable A.C.-D.C. Superhet
Radio Service Data Sheet
March 1936 Radio-Craft