RCA Victor Model 261, 555 to 107 Meter, Dual-Range, 10 Tube Superheterodyne
Radio Service Data Sheet
April 1934 Radio-Craft

April 1934 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.

I have been scanning and posting Radio Service Data Sheets like this one featuring the RCA Victor Model 261, 555 to 107 meter, dual-range, 10-tube superheterodyne radio receiver for many years now (image to the left is from the RadioMuseum.org website). 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.

RCA Victor Model 261, 555 to 107 Meter, Dual-Range, 10 Tube Super.

A frequency-range switch is the top control. Turn it clockwise for the 540 to 1.500 kc, broadcast band; using the range numerals, the dial scale reads directly in kc. for this band. Turn clockwise for the 1.400 to 2,800 kc. bands (services 1, 2 and 3, below) ; using the small numerals at the bottom of the dial, add 2 ciphers to obtain the kc, reading. The three services men-tioned above are as follows: (1) police caUs-l,574 to 1,712 kc., and 2,400 to 2,500 kc.; (2) amateur phone-l,800 to 2,000 kc.; (3) aviation phone-2,500 to 2,800 kc. (Strong local stations in the broadcast band may be sometimes heard at more than one point on the dial, when the frequency-range switch is set for the 1,400 to 2,800 kc. band.)

At the lower left of the panel is the silent-tuning control; next, right, the bass and treble tone controls; and, extreme right, the combined on-on and volume control.

With the silent-tuning control set in the extreme counter-clockwise position tune to a point at which no station is heard within several scale divisions, then turn the silent-tuning control clockwise until the back-ground noise just disappears. This adjusts the Inter-station noise suppression circuit.

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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RCA Victor Model 261, 555 to 107 Meter, Dual-Range, 10 Tube SuperheterodyneRadio Service Data SheetApril 1934 Radio-Craft

RCA Victor Model 261, 555 to 107 Meter, Dual-Range, 10 Tube Superheterodyne
Radio Service Data Sheet
April 1934 Radio-Craft