July 1933 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.
Here is Pilot Model B-2 Radio Service Data Sheet as featured in a 1933 edition of Radio-Craft magazine. As mentioned many times in the past, I post these online for the benefit of hobbyists looking for information to assist in repairing or restoring vintage communication equipment.
The control- and suppressor-grid voltage for all tubes is zero.
This superheterodyne receiver incorporates several interesting design features. One of the half-wave sections of V5 is used to supply direct current to the field coil of the dynamic reproducer; the other section delivers the high voltage required by the tube circuits. To reduce the hum level of the set a hum-bucking coil is incorporated in the dynamic reproducer. Resistor R2 is part of the power cord.
It is not necessary to adjust a circuit-changing switch when changing from one current supply to the other; tube V5 is in the circuit at all times.
The rated sensitivity of the model B-2 receiver is 100 microvolts-per-meter; the power output is 0.9-W. On A.C. or D.C. the line power consumption is 0.4-A.
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.