Motorola MTP700 Detailed Service Manual page 107

TRANSCEIVER 400 MHz
DC Distribution (V4_2.775V) Test
Use this test on a unit with the following symptoms: no V4_2.775V.
MTP700 Portable Radio / Detailed Service Manual
Check for 2.775Vdc on C291
(V4_2.775V) and on C340
(V4_LNODCT).
Are both voltages OK?
No
Check Q202 pin2 for
2.775Vdc.
Is the voltage OK?
No
Check Q202 pin3 for 3.3Vdc
(FILT_3.3V_GCAP3).
Is the voltage OK?
Yes
Check Q202 pin1 for 3.0Vdc
reference voltage (V4_DRV).
Is the voltage OK?
Yes
Check Q202, replace if required.
Yes
Check traces to RFCU, RXU,
TXPA; TXFE and LNODCT.
Yes
Check E205 or E214.
No
Refer to the DC Distribution
(V3_2.775V) Test flowchart.
No
Replace GCAP3 (U200).
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