Motorola Mototrbo - Page 236

1-2 Troubleshooting Flow Chart for Receiver
1.1 Troubleshooting Flow Chart for Receiver (Sheet 2 of 3)
A
With a DMM probe R0505
0.9<V<1.1
No
Yes
Check circuitry around
U0500 and the entire
shielded block for shorts
and opens before replacing
the part
With a high impedance probe
measure the RF level @ 73.35
MHz @ E0000
> -38.5 dBm
No
Yes
With a high impedance probe
measure the RF level @ 73.35
MHz @ C0500
> -49 dBm
No
Yes
Check circuitry around
FL0500 and the entire
shielded block for shorts
and opens before replacing
the part
With a high impedance probe (make sure to use x10 at-
tenuator to prevent overload (20 dB of attenuation)) meas-
ure the RF level @ 363.15 MHz @ C0449.
> 16 dBm
No
Yes
Check circuitry from C0468 till
C0448 for opens and shorts. (Pin 1
on Q0405 should have approx.
8.5V and pin 3 should have approx.
3.2 v).
With a high impedance probe
measure the RF level @ 436.5
MHz @ C0457
> -38 dBm
No
Yes
With a high impedance probe
measure the RF level @ 436.5
MHz at the intersection of
C0424, C0425, and C0456
> -38 dBm
No
Yes
B
With a high impedance
Probe, probe at
TP0010M2 @ 146.7 MHz
Check circuitry around
T0400, D0404, and
T0401 for opens and
shorts
Check for opens and
shorts from L0416 till
C0457
With a high impedance probe
measure the RF level @
363.15 MHz @ C0468
> 8 dBm
No
Yes
Refer to the VCO section
>-10 dBm
No
Yes
Refer to Audio Trouble-
shooting chart
Refer to RFIC