The following tables show the signals assigned to the back panel’s 25-pin I/O connectors.
Each line in the tables generally describes a pair of signals that should be twisted together
for best signal integrity. A common ground is provided on Pin-25 of all 8 connectors.
Table 147 J1 Filter Amp #1
Pin Type Direction Signal Name Comment
1/14 TTL Out
RFSW/GND
Command, RF
Upconvert Switch
2/15 TTL Out
RFTST/GND
Command, RF Test
Switch
3/16 TTL Out
RFTSTPP/GND
Command, RF Pilot
Pulse Switch
4/17 TTL Out
RFTSTTER/GND
Command, RF Test
Term Switch
5/18 TTL In
RFXTALFM/GND
Status, Crystal Fault
Monitor
25 — —
GND
Common Ground
Table 148 J2 Filter Amp #2
Pin Type Direction Signal Name Comment
2/15 TTL In
MULTRF/GND
Status, Multiplier
Fault
3/16 TTL In
RFLOFM/GND
Status, RF LO
Generator Fault
4/17 TTL In
RFTSTFM/GND
Status, RF Test Fault
5/18 TTL In
RFFM/GND
Status, RF
Generator Fault
25 — —
GND
Common Ground
Table 149 J3 Pedestal
Pin Type Direction Signal Name Comment
3/16 RS-422 In
ACP/ACPn
Antenna Control
Pulse
4/17 RS-422 In
ARP/ARPn
Antenna Reset
Pulse
25 — —
GND
Common Ground
Appendix H – TDWR Customizations
457