25
SECTION 5.
SERVICING INFORMATION
CAUTION:
This radio uses surface mount construction. It is recommended that servicing may be limited
to replacement of complete modules and non-surface mount components. Component level servicing
should not be attempted unless the engineer or technician is very familiar with surface mount repair
techniques and has all of the necessary specialized tools and equipment.
5.1 TEST EQUIPMENT AND TOOLS
ITEM DESCRIPTION
1. DMM
(Digital
Multi-meter)
2. Audio Generator 10 Hz To 10,000 Hz
3. Regulated DC Power Supply with Volt and Amp meters, adjustable up to 15 V @ 15 Minimum
4. AC Voltmeter Analog Type preferred
5. Test Set With Signal Generator, Frequency Counter, Watt-Meter/Load, Deviation Meter,
CTCSS/DCS. If test set is not available, separate equipment may be used for these functions,
6. Complete Set Of Small Hand Tools.
7. Temperature Controlled Soldering Iron.
8. Desoldering Braid Or Vacuum Type Desoldering Iron.
5.2 TUNING AND ADJUSTMENTS
5.2.1 GENERAL
All adjustments have been properly set at the factory and should not require readjustment in the field. If a
module has been replaced, refer to the section which covers the adjustment or tuning of that module.
Tuning tools should fit exactly. Use insulated, nonmetallic tools for all RF adjustments.
Always use an antenna or 50 Ohm dummy load for transmitter tests.
Do not key transmitter when connected to signal generator.
Connect the radio to a regulated DC power. Adjust for 13.8 volts at the power supply terminals.
Adjustments are to be made with the top and bottom covers removed.
Refer to section 5.3
DISASSEMBLY PROCEDURES.
5.2.2 VCO ADJUSTMENTS
Note: Adjustment should not be required unless parts or the entire module have been replaced.
If replacement and readjustment of the VCO, after repair is made, program wide band low and high power
test channels near the low end, center and high end of the band (six channels in all) with CTCSS of 100
Hz on all channels. Example, for VHF Band, 146-174 MHz, program channels at 146.1 high and low
power, 160.1 high and low power, and 173.9 high and low power.. Remove these channels after testing
