Audio power meter, used for testing audio and carrier equipment.
Manufactured from 1932 to 1961.
Used by the IDF during the War of Independence (1948), the Sinai Campaign (1956) and the Six Day War (1967).
Enabled load impedance measurements, since this impedance equals the impedance into which maximum power is delivered, and measurement of audio transformers loss.
Used for audio power measurements in the frequency range of 20 to 20,000 Hertz, power range of 0.1 to 5,000 milliwatts (-10 to +37 dB above 1 milliwatt) and impedance of 2.5 to 20,000 Ohms.
Manufactured by General Radio, USA, designated Type 583-A Output Power Meter.
