Note
Ham Radio, Nov 1971, p. 118.
Ham Radio, Jan 1972, p. 88.
Ham Radio , Jan 1973, p. 77.
Ham Radio, Apr 1974, p. 40.
Provides marker signals at 5, 10,. 2.5, 50, 100, 200, or 400 kHz intervals. Uses a 400 kHz crystal. Low power consumption battery operated circuit with 3.8 volt P-P output. Simple front panel calibration.