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Sparton Selectronne Receivers Models 1068 and 1068X
December 1937 Radio-Craft

December 1937 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.

Well shazam, I found a radio service datasheet that had been missed. This one for the Sparton Selectronne Model 1068 brings the grand total to 220 that have been scanned and posted here on RF Cafe. They appeared in various formats in Radio−Craft, Radio News, and Radio & Television News magazines. It was in the 1930s that pushbutton tuning appeared in most radio sets, both tabletop and floor-sitting console models. Those mechanical pushbutton tuner mechanisms were pretty impressive. The Selectronne also sported a popular visual tuning indicator called the Viso-Glo tube. It was not a true cat's eye in that the relative brightness of the tube's glow changed with the received station signal strength, rather than the width of the illuminated area changing.

Sparton Selectronne Receivers Models 1068 and 1068X

Sparton model 1068 Selectronne receiver, a new 1938 model using latest push-button tuning. The photo at extreme right of this page is a rear view of the locations of the trimmers for the tuning buttons shown in the above front view of this receiver. The 6 buttons of the Selectronne are arranged in 3 groups according to frequency limits - 542 to 900 kc., 700 to 1,300 kc., and 1,000 to 1,500 kc. The 6 taps corresponding to the desired stations must be arranged in the steel plate so that each station frequency will be included in the proper frequency group. To align, push in the Selectronne button which corresponds to the desired station and adjust for maximum response as indicated by the Viso-Glo tube; the aligning sequence is: (1) oscillator trimmer (center hole), (2) first R.F. trimmer ,(button hole), and (3) antenna trimmer (top hole). (The Viso-Glo tube and socket may be removed from its clamp and the tube turned toward the back of the cabinet for observation.) Adjust Selectronne trimmers for equal shaded area with band switch knob either in or out. During above operations the 6H6G discriminator is removed from chassis. In the event that all 6 Selectronne buttons become depressed through improper manipulation they may be released by applying a slight pressure of the fingers under the latching band which runs across the framework in front of the trimmer box. Care should be taken to prevent loosening the Selectronne adjusting screws to the point where they may become disengaged. The above-mentioned latching bar is seen in the photograph of the locations of the Selectronne trimmers. This latching bar, on the hack of the block that carries the Selectronne trimmers, is in direct line with the arrow that points to Selectronne trimmers C51 (osc.); a corner of the latching bar extends past the rear right edge of the trimmer panel.

Posted February 2, 2018

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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Sparton Selectronne Receivers Models 1068 and 1068XDecember 1937 Radio-Craft

Sparton Selectronne Receivers Models 1068 and 1068X
December 1937 Radio-Craft