Troubleshooting - JRC JHS-770S Instruction Manual

6.6

Troubleshooting

This unit is also used for the distress communication, in addition to usual communication.
Contact JRC or our agent if any problem is observed in this unit on usual operation or
inspection. Do NOT ignore or leave any problems of this unit.
Always use the specified fuse when replacing a fuse. Using a different fuse may result
in fire or malfunction.
Do not open the equipment to inspect or repair it. Inspection or repairs by anyone other
than a specialized technician may result in fire, electrical shock, or malfunction.
If internal inspection or repair is necessary, contact our service center or agents.
6.6.1 Procedures for locating malfunctions
1） First, check the power supply voltage, fuses, and connectors.
2） If there are no problems with the above, use a tester to check for errors.
The following table shows the instruments required for effect repairs and the severity of the malfunctions.
If required to locate the malfunction, with the exception of qualified service personnel, perform the following
No. 1 and 2 only.
No.
1 Faults requiring no instrument to locate
Malfunctions that can be fixed with a
2
tester and repaired
3 Malfunctions requiring special instrument
WARNING
Type of Malfunction Examples
・ Blown power supply fuse
・ Faulty contacts
・ Broken antenna cables
・ Defective switches, volume, etc.
・ Other problems that can be visually detected
・ Power supply voltage confirmation
・ Breaks in internal wiring
・ Crystal oscillator frequency error
・ Decrease in transmitting power and reception
sensitivity
・ Decrease in transmitter modulation level
・ Malfunctions in semiconductors, ICs, and similar
equipment
Maintenance & Inspection
6-9