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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June 1930 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.
These four Radiola superheterodynes use the same 6-tube catacomb, the first of this type put on the market by the Radio Corporation of America; differences lie in the mechanical arrangement of the units outside the catacomb, and in the electrical and artistic design. The "812," to which most of this material specially applies, is an entirely self-contained semi-portable table cabinet set with a battery compartment at each end. The A.F. output is obtained at a jack; a plug-operated switch changes the circuit from one A.F. to two. Another switch controls the "A" circuit. There is a master rheostat ("Battery Setting"), R3 in the diagram on this page, and also a vernier rheostat ("Volume Control") R2; the latter controls I.F. amplifier V3.
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 156 Radio Service Data Sheets as of December 6, 2016.