Note
Ham Radio, Sep 1974, p. 82.
The ASM-104 indicator is a go-no go device for marine and amateur radio systems. The indicator is designed to be left in the line at all times. When the transmitter is keyed, one red LED lights; if an antenna mismatch exists the other LED will light, indicating that the system should be checked.
The ASM-104 does not introduce any losses or mismatch to the system. Frequency range is 144 to 225 MHz. Power handling capability is 25
watts.
References
Brief description. Ham Radio, Sep 1974, p. 82.