FROM
SH.I
-
ISS 3, SECTION 502-501-101
ll
NE SWITCH
(S-G}
d e
(5
-Rl
IS-R
I
(S-W)
g.{��
<'�
425A
(MD} NETWORK
311A EQUALIZER
L 2
A
K
E
G
*
121 0---j E---121 121 121 )
(NOTE 4}
-,
(BL)
I}-
·:I _j
Rt
Mt
::,�3:
Gl- OR G3-
TYPE
HANDSET
(W)
(w)
RCVR
(R)
TRMTR
: (BK)
(S-Y)
(S)
(S)
NOTES:
I.
FOR MANUAL SERVICE, MOVE (S-BR) LEAD
FROM
r
T O RR TERMINAL
2. 500 A/B SET FACTORY-WI REO FOR RING PARTY.
501 A/B SET FACTORY-WIRED FOR NEGATIVE RING PARTY.
SEE TABLE
B
FOR CLASSES OF SERVICE NOT SHOWN.
3.
ll
NE S\11 TCH OFF-HOOK SEQUENCE:
(I)
ab
BREAKS
(2)
de
MAKES
(3)
be
MAKES
(4) f g
BREAKS
4. 425A NETWORK INCLUDES .311A EQUALIZER.
5.
STATIONS WITHOUT ANI,(R) TUBE LEAD MAY BE CONNECTED
TO
G IF RINGER OPERATION IS MARGINAL. AT NEGATIVE STAT I O N S
ON 9 6 V L O N G L I N E CIRCUITS,
t
R ) TUBE "LEAD SHOULD BE CONNECTED TO G .
S A M E TERMINALS M A Y APPEAR ON RINGER CONNECTION.
OP-
DIAL PULSE CONTACTS
ON
DIAL OFF- NORMAL CONTACTS
TPA-542628
Fig. 4-500A/B (MD) and 501A/B (MD) Telephone Sets, Connections (Sheet 2 of 2)
Page 7
SSP S02-501-101-i03_1972-07.{)7.jpg Scanned by Frank Harrell, (Cowboy Frank) Castle Rock, Colorado Jan 29, 2012 23:42:02