Receiver Performance Checks - ASTRO APX 7000 Basic Service Manual

Performance Checks: Receiver Performance Checks
5.4

Receiver Performance Checks

The following tables outline the performance checks for the receiver.
Test Name System Analyzer
Rated Audio RF Control: Gen
Output Level: -47 dBm
Freq: Selected radio RX
freq.
Mod: 1 kHz tone @ 3 kHz
dev.
Meter: AC Volts
Distortion As above, except
Meter: Ext Dist.
Sensitivity As above, except
(SINAD) Meter: SINAD
Noise Squelch Set as for rated audio
Threshold check
(only radios
with
conventional
system need
to be tested)
*
See Table 5-4 on page
Test Name System Analyzer
Bit Error rate Mode: Proj 25 Std
(BER) Floor RF Control: Gen
Output Level: -47 dBm
Proj 25 Dev: 2.83 kHz
Code: 1011 Hz PAT
Reference As above; lower the
Sensitivity output level until 5% BER
is obtained
Audio Output Mode: Proj 25 Std
Distortion RF Control: Gen
Output Level: -47 dBm
Proj 25 Dev: 2.83 kHz
Code: 1011 Hz PAT
Meter: Ext. Distortion
Table 5-5. Receiver Performance Checks
As above
As above
As above
Out of TEST
MODE; select a
conventional
system
1:5-5.
Table 5-6. Receiver Tests for ASTRO Conventional Channels*
Radio Tuner
Software (Bit Error
Rate screen) is
required
As above
Radio Tuner
Software not
used;
Radio: Out of
TEST MODE;
Select a
conventional
ASTRO channel
Radio Test Set
PTT to OFF
(center)
As above
As above
As above
Radio Test Set
PTT to OFF
(center)
As above
PTT to OFF
(center)
Meter selector to
Audio PA
Spkr/Load to
Speaker
Sec 1: 5-9
Comments
Set volume control to
3.74 Vrms
Distortion < 3.0%
RF input to be < 0.35 µV
Set volume control to
3.74 Vrms.
Set RF level to -130 dBm
and raise until radio
unsquelches.
Unsquelch to occur at
< 0.25 µV. Preferred SINAD
= 6–8 dB.
Comments
BER < 0.01%
(Use test setup shown in
Figure 6-1 on page 1:6-1)
Output level < 0.35 µV
(-116 dBm)
(Use test setup shown in
Figure 6-1 on page 1:6-1)
Distortion < 3.0%