Philco TB-2
Photo courtesy of Chuck at myvintagetv.com
Philco was the only "main line" TV maker to produce boosters. This 1948-9 model is one of the earliest I've found (though it begs the question, "where is the model TB-1?"). The simple, though nicely painted, metal box speaks of the early days of television, where utility trumped styling. Having no internal power supply, it was designed to steal voltage from the TV set's audio output tube socket. The input and output terminals are mounted on top and in full view, along with the twin 6AK5 tubes. No on/off or in/out switching is provided.
Capacitor tuning is used, with separate tuning for high and low bands on the same shaft, arranged to provide "continuous tuning." There are separate inputs and outputs for the high and low bands, an arrangement I have not seen elsewhere. The input of each side is untuned, through a balun, with the tube's plate circuit containing an air-wound coil and the tuning capacitor section.
Updated February 13, 2004