Service manual

8000 SERIES RECEIVER DECODER MODULE (RDM)
2-9
March 2000
Part No. 001-3139-502
6. Using a DC voltmeter, verify that 4V ±.2V is mea-
sured at TP1.
7. Adjust T5 on the receiver board if necessary.
8. If T5 was adjusted, repeat Step 4.
2.11.5 FSK LEVEL
NOTE: Before this test can be performed, the Receive
Audio Level test must be completed.
1. On the Decoder board set S1, Sections 1 "Off",
2/3 "On" and reset the RDM.
2. Using a transmission test set, verify that -20 dBm is
measured at TP4.
3. Adjust R46 if necessary.
4. On the Decoder board, set S1, Sections 1-3 to "On"
and reset the RDM.
2.11.6 RSSI LEVEL DETECTOR
1. Set the IFR signal generator to the receive channel
frequency with an output modulation set to 1 kHz at
±1.5 kHz deviation for 900 MHz or ±3 kHz devia-
tion for 800 MHz at a level of -70 dBm.
2. Connect the generator to antenna 1 (J6).
3. Verify that S1 on the receiver board is set to
"Ant 1".
4. Connect the SINAD meter from the IFR to the
Audio Output.
5. Adjust the generator until -10 dB is read on the
SINAD meter.
6. Connect an Oscilloscope or DC voltmeter to TP8.
7. Verify that TP8 is toggling between 0 and 1.
NOTE: A low, 0, on TP8 is active, indicating SINAD is
greater than the measured value. Toggling indicates
SINAD is equal to the measured value.
8. Adjust R72 if necessary.
9. Adjust the generator until -15 dB is read on the
SINAD meter.
10.Connect an Oscilloscope to TP7.
11.Verify TP7 is toggling between a 0 and 1.
12.Adjust R84 if necessary.
13.Adjust the generator until -20 dB is read on the
SINAD meter.
14.Connect an oscilloscope to TP5.
15.Verify that it is toggling between a 0 and 1.
16.Adjust R96 if necessary.
17.Adjust the generator until -25 dB is read on the
SINAD meter.
18.Connect an oscilloscope to TP6.
19.Verify that TP6 is toggling between a 0 and 1.
20.Adjust R108 if necessary.
2.11.7 RDM OPERATIONAL MODE
1. On the Decoder board set S1, Sections 1-3 "Off"
and reset the RDM.
2.11.8 RDM FINAL ALIGNMENT
1. Set the IFR signal generator to the receive channel
frequency with an output modulation set to 1 kHz at
±1.5 kHz deviation at a level of -70 dBm for
800 MHz RDM or 1.3 kHz for 900 MHz RDM.
2. Connect the generator to antenna 1 (J6).
3. Verify that S1 on the Receiver board is set to
"Ant 1".
4. On the RDM, set S1, sections 1/2 "On", 3 "Off" and
press the Reset (S3).
5. Using a transmission test set adjust R29 for
-20 dBm at TP3.