Signal/Data Activity Check - Watkins-Johnson Company WJ-8718-19/FE Instruction Manual

WJ-8718-19/FE HF RECEIVER
MAINTENANCE
Connect the receiver to a remote control unit such as
the WJ-9195C. Place the receiver in remote mode and
verify data transfer from the controller to the receiver.
Using the oscilloscope, verify the signal/data activity
using Table 4-37. Activity should be checked when
sending commands from a remote terminal.
Table 4-37. Signal/Data Activity Check
Test Point
Normal Signal
Key Component
Comments
Jl-3,4,5,
9,11
Rapidly changing
logic levels
Remote Controller
Ensure that controller is
is working properly.
Jl-15
Clock pulse
n ti it
Pin 17 on
U3-U6
Changing logic
U3-U6
U9-11
Clock pulse
U8
U9-Q0 to Q5
Sharp, negative
going pulses
U9
Data latch output
Pin 6 of
01,02
Negative going
pulses
U7,U8,U12
Address decoder
U10-7,9
Negative going
pulses
U8.U11.U10
Address decoder
PA,PB,PC
inputs of
01,02
Rapidly changing
logic levels
U3-U6
4.3.4.30
7. When the Sync Serial I/O has been repaired and is
operating satisfactorily, deenergize the receiver and
disconnect test equipment, if no further tests are to be
performed.
Front Panel Encoder Bd.t MFP-AlAl, (796056) Testing and Troubleshooting
Front Panel Encoder Board Testing and Troubleshooting includes a
checkout procedure and fault isolation information. An Oscilloscope (Table 4-1) are
required to perform the tests outlined below.
The testing and troubleshooting information in this paragraph is keyed to
following guidelines used to isolate the module fault to a defective integrated circuit or
functional group of integrated circuits. Perform the following procedure in the
sequence given.
4-55