Note
QST, Oct 1958, inside back cover.
CQ, Oct 1958, inside back cover.
QST, Nov 1958, inside back cover.
QST, Dec 1958, inside back cover.
Allied Radio catalog 1959 (issued in 1958), p. 375. (list of converters)
QST, Jan 1961, inside back cover.
QST, Apr 1962, inside back cover.
Allied Radio catalog 1963 (copyright 1962), p. 284.
Allied Radio catalog 1964 (copyright 1963), p. 221.
The NC-303 added new features to the NC-300 and changed others. It eliminated the 2215 kHz IF crystal filter and added a Q-multiplier in the 80kHz IF. A separate SSB/CW noise limiter was added, and the AVC circuit improved. It covered the 160–10 meter ham bands and included a 5 MHz wide tuning range to use with optional 6, 2, and 1-1/4 meter converters. Calibrated tuning scales for the VHF bands were included.
References
Brief description. Radio News, Dec 1958, p. 108.
Brief description. Popular Electronics, Dec 1958, p. 139.