Tx Rf - Motorola ASTRO XTS 5000 Detailed Service Manual

6-26
6.27 TX RF—Page 2
1
Measure
RAWB+
at U102-6
RAWB+
about
7.2 Vdc?
Yes
Measure
TX7V at
U102-14
TX7V
about
7.2 Vdc?
Yes
Measure
Vgate at TP111,
normally 4 to
5.5 Vdc
Vgate
> 4 Vdc?
Yes
DC bias is OK,
control is OK,
RFIN is OK, driver
has low gain
Replace
U102
April 15, 2002
No Check
continuity
No
3
No
4
Troubleshooting Charts: TX RF—Page 2
2
Measure
RAWB+
at Q107-drain
RAWB+
No
about
7.2 Vdc?
Yes
Measure
gate bias
at L108
V.gate
No
about 2 to
3 Vdc?
Yes
DC bias is OK,
control is OK,
RFIN is OK,
PA has low gain
Replace
Q107
MAEPF-27420-O
Check
continuity
Check
continuity
68P81094C31-O