15 December 1965
ITEM NAME: AMPLIFIER-INDICATOR GROUP
Synchro Control Data - One speed and
alternate trace presents IFF return signals and/or
16-speed synchro ant. azimuth data from
mapping information, as desired, and rotates with the
antenna of the Interrogator Set or with the map table of
IFF Trigger - Positive, 20v, 1 usec trigger
the Electronic Mapping Group.
preceding ea radar by either 12.2 usec or
display capability greatly increases the operational utility
36.6 usec as selected by Trigger Select
of the Close Support Control Set AN/MSQ-1 of which
switch on Indicator Control
the parent Radar Set, the Interrogator Set, and the
Map Triggers - Positive, 35v, 1 usec trigger
Electronic Mapping Group are components parts.
coincident with the radar triggers.
Although designed for immediate Mark X operation with
Interrogator Set AN/MPX-7, Amplifier-Indicator Group
AN/GPA26 has provision for future SIF operation
through the use of an AN/GPA-36 Control Unit.
Siting: The AN/GPA-26 is designed for installation
in Radar Trailer K78 of Radar Set AN/MPS-9.
RELATION TO SIMILAR EQUIPMENT
Mounting: For mechanical reasons, IP-431/GPA-26,
PP-1803/GPA-26, and C-2258/GPA should be
installed in the order named.
components may be installed in any convenient
Operational Mode I - Radar only
Operational Mode 2 - Radar and IFF
The interconnecting cables should be installed last.
Operational Mode 3 - Radar and Maps
Operational Mode .1 - Radar, IFF, and
Cabling Requirements: The interconnecting cables
are of two basic types:
Input Power Requirements:
800 va of single ph, 115v, 60 cycle
inter-van cables, of which there are 5, and intra-van
cables, of which there are 21. The inter-van
Four ranges provided: of 50,000 yd,
cables provide connections to Interrogator Set
100,000 yd, 200,000 yd and 360,000 yd.
AN/ MPX-7 which is located in a separate truck.
The intra-van cables are of various lengths and
Pre-Trigger Gate - Negative, 60v, 44
are used inside the Radar Van to interconnect
usec gate occurs 18.8 usec prior to
the components of the Amplifier-Indicator Group
with one another and with the Radar Set.
PPI Triggers - Negative, 8v, 0.8 usec
triggers at 110 pps
Radar Track Gate - Positive, 3.5v, 1.6
AN/GPA-26 is designed for installation in the
usec gate, var in time with target
Radar Van of Radar Set AN/MPS-9.
constitutes a modification to the Radar Set by
Range Mark Triggers - Positive, 0.6
replacing the former PPI display system. The
usec triggers at 81.91 kc
AN/GPA-26 operates in conjunction with the
Radar Set, with an Interrogator Set AN/MPX-7,
and with a Video Mapping Group AN/GPA-30.
PRINCIPAL COMPONENTS AND PHYSICAL DATA
Azimuth and Range Indicator
Indicator Control C-2258/GPA-26
Power Supply PP-1803/GPA-26
Electronic Control Amplifier