SWITCHCRAFT, INC. 5555 N. Elston Ave. • Chicago, IL 60630
79
JACKS AND PLUGS
FAX: 773 792-2129
JACKS AND PLUGS
DIMENSIONS ARE FOR REFERENCE ONLY Inch
(mm)
JACK SCHEMATICS
JACK SCHEMATICS
Circuit Types: Jacks normally have through circuits, shunt
circuits, and/or isolated switching circuits, either individually or
in various combinations.The chart below shows schematics of
39 common jacks - many more combinations are possible, but
these are the most commonly used. A basic description of the
switching action of each jack accompanies each schematic.
Military Identification: Military specifications covering phone
jacks use a special code to describe jack functions. Jack
schematic descriptions are coded J-1 through J-13 (as
appropriate) to coincide with Federal Item Identification
Guides for Supply Cataloging. One or more groups of suffix
numbers/letters identify isolated switching circuits used.
Suffixes identify the switching by industr y recognized notation,
i.e., 1-A, 1-B, 1-C, 1-D, etc. See chart below.
JACK SCHEMATICS
Notation Meaning
1-A One, SPST switching circuit. Also known as NO
(normally open) or “make” circuit.
1-B One, SPST switching circuit. Also known as NC
(normally closed) or “break” circuit.
1-C One, SPDT switching circuit. Also known as transfer
or “break” before “make” circuit.
1-D One, SPDT switching circuit. Also known as “make”
before “break” circuit.
Single open circuit. (J1.) Single closed circuit, Single closed circuit. (J4). Double open circuit. (J2). Single open circuit.
sleeve common. (J3). Isolated switching
“make” circuit. (J1-1-A).
Transfer circuit. (J5). Tip closed, ring Tip closed, ring open Single open circuit. Double closed circuit,
open. (J10). (common to sleeve). (J6). Isolated switching ring common to
“break” circuit. (J1-1B). sleeve. (J13).
Single closed. Isolated Double closed Single closed circuit. Double closed circuit. Double open circuit.
switching “make” circuit. (J7). Isolated switching Isolated switching Isolated switching
circuit. (J4-1A). transfer circuit. (J4-1C). “break” circuit. (J7-1B). transfer circuit. (J2-1C).
NOTE: Number indicates the quantity of circuit - 2-A means 2, A circuits.
Terminals locations shown on jack schematics do not necessarily coincide
with physical locations on jacks. Not all circuit types available on all jacks.
Double open circuit. Single closed circuit Single closed circuit– Single open circuit. Double open circuit.
Isolated switching– Isolated switching “make” before Isolated switching Isolated switching
separate “break” and “break” circuit. (J4-1B). “break”. (J8). transfer circuit. (J1-1C). “make” circuit.
make circuits (J2-1A-1B). (J2-1A).
Double open circuit. Double closed circuit. Single closed circuit Single open circuit. Single closed circuit.
Isolated switching– Isolated switching plus “make” before Isolated switching– Isolated switching
separate “make” “make” circuit on ring “break”. Isolated separate transfer and “break” circuit. Sleeve
circuits on both tip and spring. (J7-1A). switching–“make” “make” circuits. common to isolated
ring. (J2-2A). before “break” (J1-1A-1C). switching circuit throw.
circuit. (J8-1D). (J4-1B).