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LBI-38861C
Test Set Equipment List
1. Test Set, Marconi TF 2955
2. Volt Ohm and Amp Meter, AVO 8
3. Power Supply, Farnell LS30-10
Test Equipment Setup
Refer to Figure 4, Discrete List or Figure 5, Test Set.
1.
Connect power supply as shown with the positive
lead of the power supply connected to the 10.8V
terminal and the negative lead to the radio chassis.
2.
Connect the audio and PTT connections to the 6-pin
accessories socket on the top panel as indicated be-
low.
Pin 1 - Transmitter audio microphone load, 600
ohm impedance
2 - Not used
3- Receiver audio speaker load, 8 Ohm im-
pedance
4,6- Ground
5 - PTT
3.
Set the modulation level of the signal generator for
3.0 kHz deviation for 25 kHz channel spacing.
If a component has been changed to provide different
channel spacing or operating frequency be sure the associ-
ated components in the receiver and transmitter have also
been changed. Refer to the Parts List to identify the correct
components.
EEPROM Program Verification
Be sure the EEPROM has been programmed to customer
specifications, otherwise use a test EEPROM programmed
with the low, center and high RX/TX frequencies for that
split prior to aligning the radio.
When Channel Guard checks are required use the CG
frequencies listed below for test operation.
Lowest RX/TX frequency channel
67.0 Hz CTCSS
Middle RX/TX frequency channel
DCS Code 072
Highest RX/TX frequency channel
250.3 Hz CTCSS
10
Channel Guard tones and codes are given in Tables 5 and
6.
Table 5 - Standard CTCSS Tones
Freq.
Freq.
Freq.
Freq.
No.
No.
No.
No.
(Hz)
(Hz)
(Hz)
(Hz)
01
67.0
11
97.4
21
136.5
31
192.8
02
71.9
12
100.0
22
141.3
32
203.5
03
74.4
13
103.5
23
146.2
33
210.7
04
77.0
14
107.2
24
151.4
34
218.1
05
79.7
15
110.9
25
156.7
35
225.7
06
82.5
16
114.8
26
162.2
36
233.6
07
85.4
17
118.8
27
167.9
37
241.8
08
88.5
18
123.0
28
173.8
38
250.3
09
91.5
19
127.3
29
179.9
10
94.8
20
131.8
30
186.2
Table 6 - Standard DCS Codes
No.
Code
No.
Code
No.
Code
No.
Code
1
023
21
134
41
306
61
503
02
025
22
143
42
311
62
506
03
026
23
152
43
315
63
516
04
031
24
155
44
321
64
532
05
032
25
516
45
343
65
546
06
043
26
162
46
346
66
567
07
047
27
165
27
251
67
607
08
051
28
172
28
364
68
612
09
054
29
174
49
365
69
624
10
065
30
205
50
371
70
627
11
071
31
223
51
411
71
631
12
072
32
226
52
412
72
632
13
073
33
243
53
413
73
654
14
174
34
244
54
423
74
662
Table 6 - Standard DCS Codes (Con't)
No.
Code
No.
Code
No.
Code
No.
Code
15
114
35
245
55
431
75
16
115
36
251
56
432
76
17
116
37
261
57
445
77
18
125
38
263
58
464
78
19
131
39
265
59
465
79
20
132
40
271
60
466
80
81
82
83
TRANSMITTER PERFORMANCE
TESTS
POWER OUTPUT
1.
Set the power supply voltage to 10.8 Vdc. Monitor the
power supply voltage during transmit.
2.
Press the PTT switch and record the output power. The
nominal outputs are 1 or 5 Watts.
3.
Reduce the power supply voltage to 8.86 Vdc and verify
check that the power output is above 65% of the re-
corded output power.
4.
Release the PTT switch.
PEAK DEVIATION
1.
Using the channel switch on the radio select the channel
with lowest frequency.
2.
Connect the oscilloscope to the deviation meter, refer
to Figure 4.
3.
Set the audio signal generator to 1 kHz at 3 kHz devia-
tion.
4.
Press the PTT switch and observe the oscilloscope
display for a noise free 1 kHz audio tone.
5.
Set the audio signal generator output level to 3 kHz
deviation and sweep from 300 Hz to 3 kHz. Record the
peak deviation.
6.
Check the peak deviation. It should be less than 5 kHz.
664
7.
Release the PTT switch.
703
8.
Select the channel with the highest TX frequency and
713
repeat steps 3-7.
723
NOTE
It may be necessary to notch the fundamental signal
731
during this test.
732
734
SPECTRUM TEST
743
1.
Connect a spectrum analyzer and RF power meter to
754
the antenna (ANT) socket, refer to Figure 4.
2.
Press the PTT switch. Observe the output on the spec-
trum analyzer.
3.
All spurious signals and harmonics should be below -36
dBm.
4.
Release the PTT switch.
RECEIVER PERFORMANCE TESTS
SENSITIVITY
The SINAD or noise quieting sensitivity performance test
may be used to test the sensitivity of the receiver.
SINAD Sensitivity
1.
Connect the RF signal generator to the coupler as shown
in Figure 4.
2.
Set the RF signal generator to the receive frequency of
the selected channel.
3.
Connect the leads of the SINAD meter to the speaker
through the adaptor socket on the top panel.
4.
Press the monitor socket and set the volume control to
mid-range.
5.
Set the deviation for 3 kHz.
6.
Set the audio generator to 1 kHz.
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