Philips PRM80 Series - Modulation Alignment

4.5.7 Transmit Modulation Alignment (No CTCSS)
Step
No
Result
Measured by
Result
Measured at
Adjust
Result Notes
1
Switch on power
select ch.
Select ch.2 on VHF
Select ch.3 on UHF
2
Microphone
socket SK201
PIN 8
AF sig. gen.
output
1 kHz at
400+/- 40mV
rms
3
CRO
Vac per div.
0.5mSec per div.
1 x probe.
PIN 1 of
SK400
Activate PTT
Adjust 8316.
Adjust R322.
Peak,
approx 5V p.p.
Waveform should be
square.
4
CRO,
5mV ac per div.
0.5mSec per d'
1 x probe.
TP401 R567
Null in
amplitude
typ. 1 mV p.p.
A stepped sine wave
will be seen.
5
Deviation
monitor.
Antenna
socket SK402
R316
a)+/- 4.8kHz
+0/-0.2
b)+/- 3.8kHz
+0/-0.2
c)+/- 2.4kHz
+0/-0.1
a) 25/30 kHz channel
spacing
b) 20kHz channel
spacing
c) 12.5kHz channel
spacing
6
Deviation
monitor.
Antenna
socket SK402
AF sig. gen.
output freq.
300Hz to 3kHz.
Output level
400 +/- 40mV rms
Less than
a)+/- 5.0kHz
b)+/- 4.0kHz
c) +/- 2.5kHz.
a) 25/30kHz channel
spacing
b) 20kHz channel
spacing
c) 12.5kHz channel
spacing.
7
AF sig. gen.
output.
1 kHz freq
40 +/- 4mV rms.
8
Deviation
monitor.
Antenna
socket SK402
R322
a)+/- 3.0kHz
+/- 0.2kHz
b) +/- 2.0kHz
+/- 0.2kHz
c) +/- 1.5kHz
+/- 0.1 kHz.
a) 25/30kHz channel
spacing
b) 20kHz channel
spacing
c) 12.5kHz channel
spacing.
9 Disable PTT
10 FIT RADIO SCREEN TO PRM80 UNDER TEST
11
Activate PTT
12
Microphone
socket SK201
PIN 8.
AF sig. gen.
output.
1 kHz at
400 +/- 40mV
rms.
Section 4 Page 9