Part 2 Of 5; Figure 5-45. Rf Power Amplifier (Rfpa)-No Or Low Tx Power Output (700-800 Mhz)-Part 2 Of 5 - Motorola ASTRO XTL 1500 Detailed Service Manual

5-56
5.6.45 RF Power Amplifier (RFPA)—No or Low TX Power Output (700–800 MHz)—

Part 2 of 5

A
Defective parts
in matching network
between Q6500 and
Q6520?
(Note 5)
No
Q6520 bias voltages
as per Table 1?
(Note 6)
Yes
Is Q6520,
gate resistance <
1 MOhms?
(Note 7)
No
Is Q6520,
drain resistance <
1 MOhms?
(Note 8)
No
Defective parts
in matching network
between Q6520 and
Q6540-1?
(Note 9)
No
Figure 5-45. RF Power Amplifier (RFPA)—No or Low TX Power Output (700–800 MHz)—Part 2 of 5
June 15, 2005
Yes
Repair/replace
defective parts
Check/repair/replace
defective parts or
No
GOTO Power Control
- No/low VGBIAS
Chart
Repair/replace
Q6520 and retune
Yes
gate bias via
Tuner
(see help text)
Repair/replace
Q6520 and retune
Yes
gate bias via
Tuner
(see help text)
Yes Repair/replace
defective parts
Troubleshooting Charts: Flowcharts
Q6540-1 bias
No
voltages as per Table 1?
(Note 10)
Yes
Is Q6540-1,
Yes
gate resistance <
1 MOhms? and retune gate bias
(Note 11)
No
Is Q6540-1,
drain resistance < Yes
1 MOhms? and retune gate bias
(Note 12)
No
Defective parts
in matching network
Yes
between Q6540-1 and
antenna switch?
(Note 13)
No
Antenna switch
No
bias voltages as per
Table 1?
(Note 14)
Yes
B
Check/repair/replace
defective parts or
GOTO Power Control
- No/low VGBIAS
Chart
Repair/replace both
Q6540 and Q6541
(see General Notes)
via Tuner
(see help text)
Repair/replace both
Q6540 and Q6541
(see General Notes)
via Tuner
(see help text)
Repair/replace
defective parts
Repair/replace
defective parts
MAEPF-27930-O
6815854H01-A