1.2.3.7 Modulation
1. Select
Tx Power/Mod
page.
2. Select
Channel 0
.
3. Select
the
0.5W
power level.
4.
Set the microphone input signal from the Audio Generator to 1000Hz at 100mV RMS.
5.
Adjust the
VCO Modulation Limit
slider for a maximum peak deviation of
±
2.3kHz
6.
Reduce the microphone input level to 10mV RMS and check that the deviation is within the range
±
1.25 kHz to
±
1.75 kHz.
7.
Repeat steps 2 to 7 inclusive for the remaining 3 Channels (1, 2, & 3).
8.
Remove the microphone audio input signal.
9. Select
the
Generate Square Wave
function.
10. Select
PTT
and, while viewing the de-modulated signal on the transceiver test set oscilloscope, adjust
the
Modulation Balance
slider for the best square wave symmetry.
Note. DC coupling is required on the scope for optimum setting accuracy.
11.
Repeat steps 8 to 11 inclusive for the remaining 3 Channels (1, 2 & 3).