User's Manual

RPT 633
Page 5 - 6 TM1184 Issue 1
Setting up Phase Lock Loop
10. Set up the Phase Lock Loop as follows:
a) Switch on the power supply.
b) Connect the oscilloscope to TP3.
c) Adjust the slug of L1 to give 5V ±0.2V DC at TP3.
Transmitter Alignment
11. To align the transmitter carry out the following procedure:
a) Connect the oscilloscope to TP7.
d) Adjust RV3 to give 0V ±50mV DC at TP7.
c) Key ON the transmitter by shorting TP2 to TP9.
d) On FL1 and FL2 turn the four adjusters ½ turn at a time until the power meter
indicates or the power supply current increases.
e) If no power appears slightly adjust VC2 or VC3 and repeat (d).
f) Tune the four adjusters of FL1 and FL2 for maximum power.
g) Tune VC1, VC2 and VC3 for maximum power and then RV1 to give a power
meter reading of 2.5W.
h) Re-adjust VC1, VC2 and VC3 for maximum power then RV1 for 2.5W ±0.2W.
Setting Data Deviation and Centre Frequency
12. To set the data deviation and centre frequency carry out the following procedure:
NOTE: The purpose of this adjustment is to set the deviation, i.e. for 25kHz
channel spacing, to ±4.5kHz (9kHz total) when the data polarity switch is
set from "1" to "0".
a) Set LK3 of the VOX keying module to AB to select the DATA mode.
b) Connect TP14 to TP15 (+5V) to select the binary 1 state.