HF frequency meter, 125 KHz to 20 MHz, used for transmitters and receivers’ calibration.
Generates accurate frequency, used for ‘Zero beat’.
Used by the US military during WW2, designated BC-221.
Used by the IDF during the War of Independence (1948) and the Sinai Campaign (1956).
Using six BT-2 (22.5 Volts) and four BT-30 (1.5 Volts) batteries.
