example of a type designator would be RADAR Set AN/SPN-43, which is an air search
RADAR set designed for CATCC use aboard ship.
The meanings of the three letters following the slant bar may be found in Table 5-1.
Set Indicator Letter
1st Letter
2nd Letter
3rd Letter
Installation Class
Type of Equipment
Purpose
A
Piloted aircraft
A
Invisible light, heat radiation
A
Auxiliary
assembly
(department
control point use
only)
B
Underwater mobile,
B
Comsec (NSA use only)
B
Bombing
submarine
C
Cryptographic (NSA
C
Carrier Electronic
C
use only)
wave/signal
(receiving and
transmitting)
D
Pilotless carrier
D
Radiac
D
Direction finder,
and surveillance
F
Fixed ground
E
Laser
E
Ejection and/or
release
G
General ground use
F
Fiber optics
G
Fire control or
searchlight
directing
K
Amphibious
G
Telegraph or teletype
H
Recording/
reproducing
M
Mobile (ground)
I
Interphone and public address
K
Computing
P
Portable
J
Electromechanical or inertial
M
Maintenance/test
wire covered
assemblies
S
Water
K
Telemetering
N
T
Transportable
L
Q
Special or
(ground)
combination
U
General utility
M
Meteorological
R
Receiving/passa
ble detection
5-2
