Datron TW7000MS, Technical Manual

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4: Technical Description Reference/Control Board
4-12 TW7000MS
4.2 Reference/Control Board
The Reference/Control board plugs into the motherboard at J3. It is located on
the right side of the radio, second slot from the front.
In addition to the 16.777216-MHz reference oscillator, this board contains the
transceiver ALC processing circuitry, the RF power level setting
potentiometers, and the serial-to-parallel decoders that drive the harmonic
filter band-switching circuits on the RF Filter board.
4.2.1
Inter-
connections
For the interconnect lines between the Reference/Control board and the rest of
the radio, refer to the table below. If the High Stability option is installed, the
optional oscillator mounts to this board and the board is given a new part
number.
Table 4-3. Reference/Control Board Interconnects
Connector J3 Description Comment
1 Ground
2 +12V input
3 No connection No connection
4 SPICLK Clock
5 /PTT PTT
6 FB2 Filter band 2 control line
7 FB4 Filter band 4 control line
8 FB6 Filter band 6 control line
9 /TRSW T/R relay control line
10 AMPALC Input from external amplifier ALC
11 No connection No connection
12 RAWALC Transceiver ALC line
13 EN7 External amplifier filter band decoder
enable line
14 RVSPWR Reflected power indicator
15 FWDPWR Forward power indicator
16 SPITXD Serial TX data line
17 /BITE BITE line
18 FB1 Filter band 1 control line
19 FB3 Filter band 3 control line
20 FB5 Filter band 5 control line
21 FB7 Filter band 7 control line
22 No connection No connection