Operation Manual

5-9
Maintenance
Item No. Symptom Item No. Symptom
Item No. Symptom Item No. Symptom
Item No. Symptom
Possible CausePossible Cause
Possible CausePossible Cause
Possible Cause
e. Check PLL fin level at pin 8 of IC4, 245mV min
f. Defective/device: IC3-IC5, CPU (IC305), IC13-
14, Q8-13, VCO
10 a. Defective PTT switch on Handset (S727)
b.Check PTT control circuit:
1) TXD data at Q705, pin 27 of IC 706
2) PTT signal at PC304, PC306, PC308
3) RXD data at Q319-320
c. Check T8v line: Q31 output
d. Check PLL signal:5V at Q32 input, IC305 pin79
e. Check PLL unlock: IC5 pin3, unlock=51
f. Check PLL circuit: See Item 9
g.Defective/device
1) Handset: IC708, Q701, Q705-707 PC701,
PTT Sw
2) CPU PCB: IC305, PC304-309 Q316-321,
D307-312
3) RF PCB: Q31-32, PLL circuit
11 a. Check ANT cable and connector
b.Check DC line current: 25W 6.5A
c. Check LPF and Antenna switch
d. Check PA input power: 250mW typ.
e. Check power control circuit:
1) VR1-Low and VR2-High
2) APC output voltage at pin 2 of PA
3) H/L select: Q7 input (H-0V)
f. Defective/device: VR1-2, Q1-2, Q5-7, D1-6,
IC1-2 Antenna cable with connector C12-open
12 a. Check IDC inp level at pin 15 of J2 +/-3 kHz
dev: 155 mV typ.
b. Check IDC output and VR3
No transmit (TX)
Low power output (TX)
Poor or no modulation
(TX)
RAY230_sect5.p65 7/13/2001, 1:43 PM9