TM 11-5855-250-12&P
e. Differences in Searchlights.
b. Searchlight, Infrared AN/GSS-14(V) is jeep or
All models are
similar, except for the differences listed below.
tower mounted and used Control Searchlight C-
(1) Relay panel assembly 9913 consists of a
7164/GSS-14(V) which contains the mode SELECTOR
cover (mounting) plate and panel assembly to which circuit
SWITCH, the SEARCHLIGHT power switch, main power
components and the individually replaceable control relays
switch, and the override switch. It is mounted directly to
and time-delay circuits are mounted.
the rear of the searchlight subassembly and connected to
(2) Relay panel assembly model SC-D-613960
consists of a cover (mounting plate, diode CR2, circuit
breaker CB1, and the relay assembly (metal can). The
NOTE
relay assembly contains the control relays and time-delay
Some AN/GSS-14(V) use MT-3900A/
circuits that were individually replaceable in relay panel
GSS-14(V) which affects the operating
assembly 9913.
procedures for the searchlight. The
(3) On some searchlights the adjustable
operator positions the searchlight
assembly, to which the primary reflector is mounted, is
beam by manually operating the
locked in a fixed position. The clear lens located directly in
azimuth and elevation handwheels on
front of the xenon lamp has been removed.
The
the yoke. The azimuth and elevation
secondary reflector located directly behind the xenon lamp
scales can be illuminated by the scale
has been removed.
illumination switches on the pedestal.
The cable harness is routed to the
1-13. Differences in Models
control box through the mount
a. Searchlight AN/VSS-1(V) is tank mounted and
allowing the input power cable to be
connected to the pedestal.
Section III. BASIC PRINCIPLES
operating modes, and the SEARCHLIGHT power switch
1-14. General
provides the standby mode. When the SEARCHLIGHT
Operation of the searchlight consists of performing two
power switch is set from STANDBY to ON, power is
basic functions: the prime function is the ignition and
applied to the ignition circuits, causing the xenon lamp to
become lighted. When lighted, the xenon lamp produces
function is control of the searchlight modes of operation.
visible light. The light originating from the xenon lamp is
a. Ignition and Continual Illumination of Xenon Lamp.
directed into the primary reflector and projected by the
This action is accomplished within the initial three seconds
searchlight as a visible-focus beam (A, fig. 1-10). Wide-
following the application of power to the igniter circuits
beam operation, in either visible or infrared light, is
(converter and igniter assemblies and the xenon lamp).
obtained when the refractor lens is placed in the path of
The xenon lamp must go through three sequences to
the light beam (B and D, fig. 1-10). Infrared light, in either
become fully lighted: the initial ionization and start of lamp
the focus or wide-beam operating modes, is obtained
when the infrared filter is placed in the path of the light
conductance, and maintaining lamp conductance for
beam (C and D, fig. 1-10). The metal blackout shield is
placed in the path of the light beam when in the blackout
xenon lamp to produce the three sequences: 40-kilovolt
or standby modes, preventing emission of light (E, fig. 1-
(kv) radio frequency (rf) pulses, 55 volts dc, and 28 volts
10). The
override mode produces a
light of
higher
dc from the power source. The 40-kv rf pulses cause the
intensity in either the visible or infrared operating modes,
initial ionization of the xenon gas and start of lamp
by causing an increase in current through the xenon lamp.
conductance. The 55 volts dc increases the temperature
of the xenon gas and increases the level of conduction so
1-15. Equipment Functioning
that 28 volts dc from the power source can maintain lamp
a. General. When the main power switch in the tank
conductance for continual illumination. After 3 seconds,
or on the control box (fig. 1-8) is set to ON, 28 volts dc is
the components and assemblies used for the initial ignition
distributed throughout the searchlight subassemblies and
of the xenon lamp are shut off. The sequences will
the control box, which readies the searchlight for
automatically be repeated if the xenon lamp is not lighted
operation. When the SEARCHLIGHT power switch is set
within the initial 3 seconds.
b. Searchlight Modes of Operation. The searchlight
to STANDBY, 28 volts dc is applied to specific
components within the searchlight subassemblies, the
modes of operation are determined by the mode
blower motor is turned on to cool the xenon lamp, the relay
SELECTOR SWITCH and the SEARCHLIGHT power
mode SELECTOR SWITCH provides visible-focus, visible-
wide, infrared-focus, infrared-wide, blackout, and overdrive
1-12