Note
QST, Jan 1950, p. 105.
Allied Radio catalog 1951 (copyright 1950), p. 138.
QST, Nov 1950, p. 83. (HRO-50R)
QST, May 1951, page inside back cover. (HRO-50-1)
QST, Jun 1951, p. 103. (HRO-50-T1)
Allied Radio catalog 1952 (copyright 1951), p. 137.
See notes from National: QST, Jun 1950, p. 65.
See notes from National: QST, Aug 1950, p. 57.
See notes from National: QST, Sep 1950, p. 69.
See notes from National: QST, May 1951, p. 77.
QST, Mar 1950, inside back cover.
QST, Aug 1950, inside back cover.
HRO-50-1 later called HRO-50-T1.
QST, Jun 1951, inside back cover.
See notes from National: QST, Apr 1952, page 75.
HRO-50 and 50-T1 sold concurrently. See: QST, Sep 1951, p. 117.
The HR0-50 was introduced in 1950 and was the first HRO to have a direct-reading slide-rule dial in addition to the standard PW main-tuning dial. It also broke with HRO tradition by incorporating an internal power supply. The 15-tube, single-conversion set had a crystal filter and a 455 kHz IF. It tuned from 50-430 kHz and from 0.48-35 MHz using a dozen plug-in coil sets. In addition to AM and CW, the HR0-50 could receive NBFM signals when equipped with the NFM-50 adapter. 1951 saw the introduction of the HR0-50-1. The -1 models added an additional IF stage, bringing the tube count to 16, and had cascaded IF transformers for improved skirt selectivity. Optional MRR rack which has the 50SC coil cabinet and speaker; HR0-50, $349.00, HR0-50-1, $383.50.
