1996 - 2016
BSEE - KB3UON
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 Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
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February 1936 Radio-Craft[Table of Contents]
People old and young enjoy waxing nostalgic about and learning some of the history of early electronics. Radio-Craft was published from 1929 through 1953. All copyrights are hereby acknowledged. See all articles from Radio-Craft.
All necessary voltage information is given on the chassis layout diagram. The LF. amplifier is aligned by connecting the leads of a service oscillator from cap of V1 to chassis. Tune C11 and C12 for best output. Then feed a 1,400 kc. signal to antenna and ground, set receiver dial to 1;400 kc. and adjust C24 and C25 for highest output. Set oscillator at 600 kc. and align trimmer at rear of chassis. Dial reading of set should fall fairly close to 600 kc. The short-wave band will need no adjustment. On the latter band the same oscillator coil is employed, a harmonic being used for actual reception. Power transformers are available for either 25- or 60-cycle use. The power output is 1.9W. (undistorted), and 3W. (max.). The power input is 40W. at 115V. Filament circuit is novel in that the pilot light and V3 are connected to one winding, while all the other tubes are in series on another section. (Coil resistances, in parenthesis.) Two of the tubes are of multi-purpose type
Posted July 19, 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 152 Radio Service Data Sheets as of November 14, 2016.