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

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WJ-8711A DIGITAL HF RECEIVER CSMA REMOTE CONTROL
5-13
5.8.9
RESPONSE TO GAIN CONTROL MODE REQUESTS [30]
Figure 5-13 shows an example of the typical response format when requesting the receiver's
active gain control mode with control code [30].
FE
PREAMBLE
FE
RX
ADDR
TX
ADDR
CONTROL
CODE
END OF
MESSAGE
1A F1 30 00 FD
GAIN
MODE
87IL18
Figure 5-13. Gain Control Mode Request Format
The byte in the response after the control code contains the gain control code. The response
in this byte is [00] for manual gain, [01] for slow AGC, or [02] for fast AGC. In the example, manual gain
control is the response.
5.8.10
MANUAL GAIN LEVEL COMMAND WITH ACKNOWLEDGE [33]
Figure 5-14
shows an example of the typical format for selecting the receiver's manual gain
level using control code [33]. This control code requires an acknowledgment to the controller.
FE
PREAMBLE
FE
RX
ADDR
TX
ADDR
CONTROL
CODE
END OF
MESSAGE
1A F1 33 15 01 FD
100'S 1'S
87IL19
Figure 5-14. Manual Gain Level Command Format
Two bytes are sent with the control code, with the combination of both representing the value.
The range is 0000 to 0127 (for 0 to 127 dB). In the example, a manual gain level of 115 dB is selected
[15|01].
Courtesy of http://BlackRadios.terryo.org