
June 1999
68P02945C75-A
5-3
GTX/GTX LTR/LTS 2000 Portable Radios Service Manual
Performance Checks
Performance Checks
Table 5-4 Transmitter Performance Checks
TEST
NAME
COMMUNICATION
ANALYZER
RADIO
TEST SET
COMMENTS
Reference
Frequency
Mode: PWR MON
2nd channel test frequency Monitor.
Frequency error input at RF In/Out
TEST MODE,
Display: 2 0
PTT to continuous
(during the
performance check)
Frequency error to be
< 700 Hz
Power RF
Same as Above
TEST MODE,
Display: 2 0
Same as Above
Refer to Performance
Specification Page XIII
Voice Modulation
Mode: PWR MON
4th channel test frequency
atten to -70, input to rf In/Out
Monitor: DVM, AC Volts
Set 1kHz mod Out level for
0.025Vrms at test set,
80mVrms at AC/DC test set jack.
TEST MODE,
Display: 2 0
Same as Above,
meter selector to mic
Deviation:
≥
3.6 kHz but
≤
5.0 kHz
Low-Speed Data
Modulation
800/900
Same as Above
TEST MODE,
Display: 2 1
PTT to continuous
(during the
performance check)
Deviation:
≥
800 Hz but
≤
1200 Hz
Voice Modulation
(Internal)
Mode: PWR MON
2nd channel test frequency
atten to -70, input to RF In/Out
TEST MODE,
Display: 2 0
Remove modulation
input
Press PTT switch on radio.
Say “four” loudly into the
radio mic. Measure deviation:
≥
3.8 kHz but
≤
5.0 kHz
High-Speed Data
Modulation
Same as Above
TEST MODE,
Display: 2 2
PTT to continuous
(during the
performance check)
Deviation:
≥
2.3 kHz but
≤
3.8 kHz
DTMF Modulation
(# SIGN)
Same as Above
2nd channel test frequency
TEST MODE,
Display: 2 3
output at antenna
Same as Above
Deviation:
≥
2.8 kHz but
≤
3.8 kHz
PL/DPL
Modulation (radios
with conventional
coded squelch
operation only)
Change frequency to a
conventional transmit
frequency, BW to narrow
Conventional coded
squelch personality
Same as Above
Deviation:
≥
500 Hz but
≤
1000 Hz
Talk-around
Modulation (radios
with conventional
talk-around
operation only)
Change frequency to conventional
talk-around frequency.
Mode:PWR MON
deviation, attenuation to -70,
input to RF In/Out
Monitor: DVM, AC volts
Set 1kHz Mod Out level for
25mVrms at test set.
Conventional talk-
around personality
Same as Above
Deviation:
≥
3.8 kHz but
≤
5.0 kHz