Note
QST, Jun 1939, p. 2.
Lafayette catalog number 78, p. 149.
Lafayette catalog number 82, p. 113.
The HT-7 frequency standard provided marker signals at 1000, 100, and 10 kHz intervals in the 1 to 30 MHz range. The circuit used four tubes and its tuned output circuit could be resonated to desired harmonics.
References
Brief review. Radio, Oct 1939, p. 74.
Brief description. Radio Craft, Nov 1939, p. 298.
Brief description. Radio News, Nov 1939, p. 17.
