Watkins-Johnson Company WJ-8718-19/FE Instruction Manual page 180

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4.3.4.11 1 MHz Filter, FE-A3, (794327) Testing and Troubleshooting
1 MHz Filter Testing and Troubleshooting includes a checkout procedure
and fault isolation information. A Signal Generator, an RF Voltmeter, and a Digital
Voltmeter (see Table 4-1) are required to perform the tests outlined below. Perform the
procedure below in the sequence given. Refer to Figure 6-12, 1 MHz Filter Schematic
Diagram, as an aid in performing the sequence.
1. Disconnect P2 from A1J2 on the Frequency Extender.
2. Connect an RF Voltmeter and 50 ohm adapter to P2.
3. Connect the output of a Signal Generator to Jl on the
1 MHz filter.
4. Set the RF Voltmeter to the 0 dBm range.
5. Set the Signal Generator output frequency to 1.0 MHz
and output level to 0 dBm.
6. The RF Voltmeter should indicate a level between
0 dBm and -3.0 dBm.
8. If the signal in step is incorrect, check all capacitors
and the two Zener diodes for leakage to ground. Check
all inductors for continuity. Field realignment of the
filter is not practical.
9. When the 1 MHz Filter has been repaired and is
operating satisfactorily, deenergize the receiver and
disconnect test equipment, if no further tests are to be
performed. Reconnect all cables removed during testing.
4-3.4.12 Input Converter, A3. (791592) Testing And Troubleshooting
Input Converter Testing and Troubleshooting includes a checkout
procedure and fault isolation information. A Signal Generator and an RF Voltmeter
(see Table 4-1) are required to perform the tests outlined below.
Perform the following procedure in the sequence given. If any specified
result is not obtained, refer to Table 4-11 for fault isolation.
1. Deenergize the receiver.
2. Disconnect A2P1 from A3A1J1 and P28 from A3A2J2.
Terminate A3A2J2 with 50 ohms.
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