MODEL 1200-03 IF PROCESSOR
1.0 General
1.1 Equipment Description - The 1200-03 IF Processor consists of a transmit and receive side. The receive
side consists of one receive IF signal going through an Automatic Gain Control (AGC) amplifier and then
split into three signals, DIG1RX, FDMRX, DIG2RX each having variable attenuators to adjust their levels
over a 30dB output range via front panel multi-turn potentiometers. The AGC amplifier provides Automatic
Gain Control for a 50 to 90 MHz IF signal for a -80 to 0 dBm input level to a -35dBm ±10dB output. A front
panel monitor port provides a monitor signal out of the AGC amplifier.
The transmit side consists of three transmit IF signals combined into one. Transmit DIGTX, FDMTX, and
DIG2TX signals each pass through individual attenuators controlled via front panel multi-turn
potentiometers and a switch that is controlled remotely through a DB9 connector or locally with three 2PDT
switches located on the front panel.
A 2PDT switch on the front panel selects either REMOTE or LOCAL operation. On the DB9 connector a
closure to +V will turn the corresponding transmit channels on. A local override feature is included such that
when the REMOTE/LOCAL 2PDT switch on the front panel is left in the LOCAL position, the override pin
on the DB9 can be set to +V to override the LOCAL control and allow for REMOTE control. DIG1 and
DIG2 on both transmit and receive sides are 75
in/out while FDM on both transmit and receive sides are
50
in/out. When power is removed from the 1200-03, the FDM TX and FDM RX signals pass through to
the output.
The IF in and out connectors are BNC female. All circuitry is on a single PCB housed in a 1RU X 14”
deep chassis. An internal switching power supply powers the unit with a 100-240 ±10% VAC, 47-63 Hz
input.
REAR
AC IN
GND
J107
DIG1
RX OUT
J106
J105
J108
J109
FDM
RX OUT
DIG2
RX OUT
RX
IF IN
CONTROL
FRONT
MODEL 1200
IF PROCESSOR
C
ROSS
T
ECHNOLOGIES, INC.
DC
J102
DIG1
TX IN
J101
J103
J104
FDM
TX IN
DIG2
TX IN
TX
IF OUT
OVERRIDE
LOCAL
DIG2
FDM
DIG1
SW1
SW2
SW3
SW4
LOCAL
REMOTE
ON
ON
ON
TX
IF MON
RX
IF MON
J1
J2
GAIN
T3
R1
R2
R3
T1
T2
DIG1
FDM
DIG2
FIGURE 1.1 Model 1200-03 Front and Rear Panels
1200-03 Manual, Rev. B
Page 3
01/08/09
