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(c) Sindre TORP
AC Variac/Line Voltage Test Units ( two models )
The AC Variac, in the photo, was made during the days of the 4-line production, note the amber L-4 indicator lamp, as the power "on" indicator. The AC variac was used to test the operation of various units at low line voltage. The average off the shelf variac did not have a meter to monitor the actual line voltage. Therefore, the test department designed and built the variac into a box with a meter to read the line voltage.
There were various models built as production needs grew. The later units were built with digital display as the Line Voltage Test unit in the photo shows. I suspect the units with the digital display were built during the 7-line era.
The R-4 series receivers, as well as other receivers, were final tested for "calibrator fall out at low line voltage". I don't remember what other tests were done at low line voltage or how low the line voltage was reduced. If the receiver failed any part of the test, it was bounced back to the appropriate test position for correction. As a "tester" I did not like to get a "bounce" unit for any reason, but once promoted to a "final inspector" I kinda liked "bouncing" a unit back. Kept the testers on their toes!!
The receiver section of all TR-4 series transceivers was tested at low line voltage. All AC-4 power supplies were tested at low line voltage, while measuring AC ripple and DC levels. The AC variac was used through the plant on various lines, engineering department, and the QC department.
Bill Frost
02/14/2005
