Note
QST, Dec 1952, pp. 80–81.
Allied Radio catalog 1954 (copyright 1953), p. 50.
Allied Radio catalog 1955 (copyright 1954), p. 192.
The 75A-2 (1950) had introduced the dial escutcheon that would remain throughout the rest of the A-line receiver series. It covered 160-10 meters, and used the new 70E12 PTO. The optional 148C-1 adapter enabled NBFM reception. Collins' 75A-3 added mechanical filters to the 75A-2 design, ushering in a new era of selectivity for amateur receivers. It retained the previous model's crystal filter, included a 3.1 kHz mechanical filter, and offered an 800Hz filter as an option. The mechanical filters were selected by a lever switch concentric with the BFO knob.
