For Stage : PP/MP
Release Date : July 11, 2005
Page 5 of 6
5.8 Observe the voltage at TP1, the voltage should be
0.6~3.0Vdc
.
5.9 Release the PTT switch so the unit will be in receive mode.
5.10 Observe the voltage at TP1, the voltage should be
0.6~3.0Vdc
.
NOTE : Above Specifications are measured with VCO Plate soldered.
5. TRANSMITTER FREQUENCY ALIGNMENT
6.1 Set the unit at Ch1. Press the PTT button so the unit will be in transmit mode.
6.2 Adjust CT201 trimmer capacitor until such that the output frequency is equal to the
channel frequency with maximum error of +/-200Hz
(OQA Limit of +/-800Hz).
Production will control as follows:
- PCBA Alignment : +/-200Hz
- Casing Test : +/-500Hz
- OQA Limit : +/-800Hz
6. TRANSMITTER OUTPUT POWER CHECK
7.1 Set the unit at Ch1. Set the Power Supply at 6Vdc. Power is at Hi condition (use
short cable)
7.2 Press the PTT button so the unit is in transmit mode. Make sure Batt. Voltage is at
6Vdc during PTT.
7.3 Transmit Power should be
>4.5W.
7.4 Set the unit at Power Lo condition.
7.5 Press the PTT button so the unit is in transmit mode. Ensure the TX Power is within
0.3~1.0W.
7. TRANSMITTER DEVIATION ADJUSTMENT
8.1 Connect an audio generator (600ohms) to the microphone terminal pads. The audio
frequency should be set at 1kHz with a level of 200mVrms.
8.2 Connect an FM Deviation Meter (on the HP8920B) on ANT point. Set the monitor to
read
(Pk to Pk)/2
deviation. Set
Filter 1
to <20Hz and
Filter 2
to 15kHz.
De-
emphasis
should be set to Off.
8.3 Press the PTT button so the unit will be in transmit mode.
8.4 Adjust RV2 and observe the reading at the Deviation Meter, the reading should be
between 3.9 to 4.1kHz. Checking at all condition should be 3.7 ~ 4.3kHz.
8.5 Decrease the audio generator level until the deviation reads +/-3.0kHz. The
generator level should be between
3 to 10mV
.
8.6 Set the Modulation @ 2.0kHz, check that the transmit audio distortion is less than
5%.
