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INSTAIIAI I'-,$ti jti{D
OPERATIGT.'l
NAVSHIPS
As explari ,',. irli,r're, "normal through" circuits may
be readil;i alt,'ir"r iry maintenance -"tt bv moving the
ilexible lead:, irrr-i;r 1hs cabinet between the Interconn(
:ting Term,ni.i Boards AN Typ" I-242/G. Whenever
a circri* is to he in use for any length of time, a
norr rral thr', t?;it" circuit should be set up and the use
cf patchcorC, elirninated as patchcords are susceptible
tc " )osc ,' ,-fir)€ctions and unnecessarily clutter the front
of tiie eq.ripment. The flexible leads consist of twisted
pairs fitte,C with spade lugs on both ends. Connection
is rnade by merely connecting the spade lugs to the
screw terminals on the terminal boards.
NOTE
If the flexible leads have been properly fabricated
by the installing activity, one of the
spade ltrgs is clipped on the opposite ends of
the lead to indicate polarity. Connect to corresponding
terminals so that polarity will not
be reversed.
(a) NORMAL THROUGH CIRCUIT AL-
TERATIONS.-Figure 2-22 shows the ideal 'hormal
through" circuit in which the flexible leads are connected
straight through. This is desirable, but if it is
found that some other connection will be used for
some time, it is desirable for maintenance men to
change the "normal through" circuit rather than relying
Lrpon patching. For example, as shown in figure
2-23, suppose that it is desirable to exchange the loads
of circuits " \" and "C". This exchange may b" readily
made by maintenance men by exchanging the connection
of the flexible leads as sho'wn in figure 2-23.
(2) PATCFIINC OPERATION.--F i g u r e 2 - 2L
shows the wiring convention for the Receiver Output
and Miscellaneous App'raratus j ack Panels. Figure
2-24 shows the operation of the jp.'k'- .n the Receiver
Output and N{iscellaneous Appa'atus }ar:k Panels as
instalied and wired. It can be seen that rnsertion of a
patchcord plug into the bottorn jack establishes a parallel
connection, while insertion into the top jack interrupts
the "norrnal tir ough" circuit arrd substitutes anoiher
circuit in its place.
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Flgur+ 2 ".ll'i. *",f ir .i:'i,.r Convention For AF
T}R'GiNAi.
INTERCONNECTING
TERMINAL BOARD
J-24il G
Jqck Pqnefs
RESTRICTED
9ro47
RECEIVER OUTPUTS
CONTROLS A N TYPE
LOAD CIRCUITS
Figure 2-23. chonging "Normql Through" circuits
by Altering Flexible Connections
The audio section is wired so that in all cases the top
row of jacks substitutes a new circuit for a "norrnal
through" circuit while the bottom row parallels a circuit
to the "normal through" circuit. The twin pronged
patchcord is always inserted so that the plane of the
prongs is horizontal as shown in figure 2-25,
When inserting a patchcord plug, make sure that it
is inserted into the proper pair for that circuit and
does not split between adjacent pairs. The patchcord
plugs have notches cut into them on one side to indicate
polarity. Always insert the patchcord'so that the
notches are to the right.
AF Patchcords Navy Typ" -4gl3g7A which are
mounted in special storage panels are provided for
normal patching operations. These cords are B feet
long. Additional patchcords are provided in spares
for patching where this length will not reach or if the
number provided is insufficient. These are as follows:
Type
-491397
-4913978
-49r397C
FROM
c-4 43/G
og 9 9 o o o o o
RECE IV E R
AN TYPE
Section 2
Porogrqph 2 c (l)
Length
24"
48"
72"
OUTPUT T.B.
J-242 lG
RECEIVER OUTPUT JACK PANEL
(JACK MOUNTING STRIP N.T. -
49t394)
INTERCONN ECTING T. B.
A N TYPE J-242 lG
"NoRMAL THRoUGH"
CONNECTIONS STYITCHED
INTE R CON N ECTING T. B.
AN TYPE J-242/G
MISC. APPARATUS
(JACK MOUNTING
4 9t594!
MISC. APPARATUS T.B.
AN TYPE J-242lG
JACK PANEL
STRIP N.T -
2-23