Motorola GP88s, Service Manual

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5-4 Test Mode
* See Table 5-4
Table 5-5 Receiver Performance Checks
Test
Name
Communications
Analyzer
Radio Test Set Comments
Reference
Frequency Mode: PWR MON
4th channel test frequency*
Monitor: Frequency error
Input at RF In/Out TEST MODE,
Test Channel
4 carrier
squelch out-
put at
antenna PTT to continu-
ous (during the
performance
check) Frequency error to be
±200 Hz VHF
±600 Hz UHF
Rated Audio Mode: GEN
Output level: 1.0mV RF
4th channel test frequency*
Mod: 1kHz tone at
3kHz deviation
Monitor: DVM: AC Volts TEST MODE
Test Channel
4 carrier
squelch PTT to OFF
(center), meter
selector to
Audio PA Set volume control to
3.16Vrms
Distortion As above, except to distor-
tion As above As above Distortion <3.0%
Sensitivity
(SINAD) As above, except SINAD,
lower the RF level for 12dB
SINAD. As above PTT to OFF
(center) RF input to be <0.35
µ
Noise
Squelch
Threshold RF level set to 1mV RF As above PTT to OFF
(center), meter
selection to
Audio PA, spkr/
load to speaker Set volume control to
3.16Vrms
As above, except change
frequency to a conventional
system. Raise RF level from
zero until radio unsquelches. out of TEST
MODE; select
a conven-
tional system As above Unsquelch to occur at
<0.25
µ
V.
Preferred SINAD =
9-10dB