Comtech EF Data ROSS - Manual (Page 79)

ROSS MN/13070
ROSS to ACU Hardware Controls Signals
The Sea Tel DAC-2202 supports blocked, pointing error and RF radiation hazard carrier muting
signaling function on a 25 pin terminal mounting strip (TB2). Also modem lock input for
positive satellite ID. (See Sea Tel document DAC-2202 ACU for more details).
To comply with FCC CFR part 25.222(a6)(a7), cease carrier transmission through pointing error
or blockage, this hardware level (TTL) interface is connected to the ROSS unit through hardwire
connections. The ACU shorts pin SW2 to GND (on TB2-Terminal Mounting Strip) when
antenna is outside the configured pointing limit of 0.5 degree from satellite peak or limit stop
blockage occurred, thus muting modulator carrier output.
CDM-570 Satellite Signal Identifier Connection
The modem rear panel RX Traffic Alarm indicator connector pin 15 (RX-NC, Locked) is pulled
low (grounded) by the modem when demodulator lock is detected, this is used as a positive ID to
the antenna controller to stop tracking and peak on signal. When RX Traffic is faulted, (RX-NO,
Unlocked) the signal to the ACU (EXT AGC, TB2) is pulled high indicating demodulator
unlocked condition, within ~20 seconds the ACU will commence retargeting of the antenna.
SLM-5650A Satellite Signal Identifier Connection
The modem rear panel Auxiliary connector J9-HD-15F (Rx TTL Fault) is logic Low when not
faulted indicating demodulator lock, this is used as a positive ID to the antenna controller to stop
tracking and peak on signal. When RX is faulted, the signal to the ACU (EXT AGC, TB2) is
pulled high indicating demodulator unlocked condition, within ~20 seconds the ACU will
commence retargeting of the antenna.
ƒ External AGC input must be 0 to 5 Volts DC analog signal, positive going voltage
proportional to satellite signal input level and must be real-time in its response to antenna
pointing.
ƒ External Modem Lock from a satellite modem is used as a positive ID that the antenna is
on the desired satellite. This input is NOT used for tracking purposes; it is only used for
satellite identification to acquire the correct satellite during search. To enable the external
modem input you must the ACU SYSTEM TYPE parameter to 79 and NID MUST be set
to 0000 indicating no DVB NID used.
o Lock Logic - The modem lock signal connects to EXT AGC and a ground
reference from the modem connects to GND. The expected signal from the
modem is 0VDC to +5VDC. Low voltage indicates modem lock, high voltage
indicates modem unlock.
Comtech EF Data, Vipersat Products Page 79 of 87