I purposely did not mention the details of "S-Meter alignment", since this is a little complicated.
It has to be performed on each band individually and you need a signal generator to do it properly.
Enter alignment mode as described in my previous article and switch to A-7 SM L/V
For 70cm S-Meter adjustment:
Tune the "right" band frequency to 440.050 MHz
Inject an RF-signal of -5 db-microvolt into antenna input, freq. 440.050 MHz.
Press the "left" band [LOW] key, then adjust the "left" dial knob so that the Smeter deflects 1 dot.
Increase the RF generator output level to +23 db-microvolt.
Press the "left" band [V/M] key, then adjust the "left" DIAL knob for full scale Smeter deflection.
For 2m. S-Meter adjustment:
Tune the "right" band frequency to 146.050 MHz
Inject a 146.050 MHz signal at a level of -5 db-microvolt from the RF signal generator.
Press the "left" band [LOW] key, then adjust the "left" DIAL knob for 1-dot S-meter deflection.
Increase the RF-generator output level to +23 db-microvolt.
Press the "left" band [V/M] key, then adjust the "left" DIAL knob for full-scale Smeter deflection.
IMPORTANT:
Repeat this procedure by tuning the "left" band frequency to 440.050 MHz and 146.050 MHz, but this time use "right" DIAL knob for S-meter deflection adjustment. Do the same adjustments as described, changing RF-generator output from -5 db-microvolt to +23 db-microvolt (S1 or S9+).
The same procedure applies for 28 MHz & 50 MHz, but for "left" band frequency only. (28 & 50 MHz cannot be used in sub-band) Remember: you NEED a calibrated RF-generator for proper adjustment.!
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