Field Strength Measurement Mode

TM 11-6625-2946-14/TM 08168A-14/1

The mixer output is then attenuated to provide the rf

meter deflection corresponding to the rf power level

received; therefore, in the use of the FSM, the red and

output to the radio set receiver at the ANTENNA con-

nector.

green portions of the meter scale are not significant. In

the use of the FSM for coupler adjustment, the ad-

4-6. Field Strength Measurement Mode

justments are made for maximum deflection on the

The field strength measurement (FSM) mode provides

meter. To avoid effects from the meter-protection

measurement of the radio set radiated power for

limiter of the field strength measurement circuit and

monitoring its output in the adjustment of the radio set

from signals radiated from the radio set internal cir-

antenna coupler. The radiated rf signal is received by the

cuitry, the FSM should be operated at a meter reading

level of 7 units or less by increasing the distance between

test set antenna and converted to a dc level by the field

the test set and the radio antenna.

strength detector circuit. The detected dc current causes

4-3