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Description
Four-tube, breadboard transmitter, VT-4C 50-watt output, crystal controlled, 3622 kHz (80 meters). Believed to have been constructed in the mid to late 1930s. This is a one-of-a-kind amateur radio breadboard, likely built as a demonstration unit, possibly for educational purposes. The unit can be changed from crystal-controlled, fixed frequency operation to variable frequency by removing the crystal (front left) and moving the coil on the far left into the empty socket next to it. A light bulb can be screwed into the empty socket on the far right to demonstrate the flow of current through the unit. An antenna connection is at the back, but it is unlikely that this was used for actual transmission. The first vacuum tube is an oscillator, the second one an amplifier. The third tube drives current through to the fourth tube amplifier that carries the final power load. This would have been expensive to construct at the time, and the builder appears to have purchased all of the base components from the same supplier.
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