Watkins-Johnson Company WJ-8711A, Installation, Operation And Maintenance Manual

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WJ-8711A DIGITAL HF RECEIVER CSMA REMOTE CONTROL
5-9
5.8.3
RESPONSE TO TUNED FREQUENCY REQUESTS [03]
Figure 5-7 shows an example of the typical response format when requesting the tuned
frequency with control code [03].
FE
PREAMBLE
FE
RX
ADDR
TX
ADDR
CONTROL
CODE
VARIABLE LENGTH
DATA
END OF
MESSAGE
FD
1A F1 05 50 34 12 14
x 1 Hz x 1 MHz
87IL12
Figure 5-7. Tuned Frequency Request Response Format
The response in the example is 14.123450 MHz. The first byte of the frequency data contains
Hz data. The last (fourth) byte contains MHz data. The response always contains all four bytes of the
frequency data.
5.8.4
RESPONSE TO TUNED FREQUENCY RANGE REQUESTS [02]
Figure 5-8 shows an example of the typical response format when requesting the tuned
frequency range of the receiver with control code [02].
In the response the upper frequency limit and the lower frequency limit are separated with 2D
hex. The first byte of the frequency data in each limit of the response contains Hz data. The last (fourth) byte
contains MHz data. The upper frequency limit response always contains data representing 30.000000 MHz
[00|00|00|30]. The lower frequency limit response always contains data representing 0 Hz [00|00|00|00].
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