Charles 7305-14 4W-2W, Manual

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Section 730–514–202
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4.6 Power Supply
The on-board REGULATED POWER SUPPLY derives the necessary voltages to operate the CFMs from a
–48VDC (nominal) source and power return ground applied at pins 35 and 17 respectively.
4.7 2713Hz Tone Activated Loopback (7305–19 Only)
The 7305–19 provides tone-operated loopback toward the 4W facility. A continuous 2713Hz loopback control sig-
nal applied to the RCV LINE for a minimum of 2 seconds satisfies the first condition for loopback operation. Upon
removal of the 2713Hz tone, the final condition is satisfied, operating and latching the LB RELAY and illuminating
the LB LED. The LB RELAY performs the following functions while operated:
Loops all voice-band signals from the RCV STA to the XMT STA at equal loopback levels. Up to
+/–24dB gain (switches S101 and S102) is provided to accommodate a full range of TLPS.
Opens the RCV STA and XMT STA paths to the equipment, preventing transmission.
Internally conditions the E&M leads to loopback the signaling circuit.
Busies the E or M lead to the station equipment.
Loopback release is accomplished by the reapplication of 2713Hz tone to the 7305–19. After the 2713Hz tone is
received for approximately 0.9 seconds, the LB RELAY releases and the LB LED extinguishes, ending the loop-
back condition.
The LOOPBACK LEVEL AND CONTROL is conditioned by DIP switch S103. The tone detector can be disabled
by placing the DTD switch of S103 to the IN position. Manual loopback can be enabled by placing the MLB switch
of S103 to the IN position. The LOOPBACK LEVEL AND CONTROL also contains a four minute time-out function
that, when enabled, will automatically reset the loopback to its normal condition four minutes after the tone acti-
vated loopback is started. This function is enabled by placing switch T/O of S103 to the OUT position. Time-out is
20 minutes with T/O of S103 in the IN position.
5. MOUNTING
The 7305–14 and 7305–19 are 400-type plug-in combined function modules (CFMs) designed to mount in
TL40XX Mounting Assemblies. They can also be mounted in one position of unwired 400-type mounting assem-
blies or in the transmission position of 72 Family Mounting Assemblies.
Installation and removal of modules should be done with care. Do not force a module into place. If
excessive resistance is encountered while installing a module, remove the module and check the card
guides and connector to verify proper alignment and the absence of foreign material.
CAUTION
6. INSTALLER CONNECTIONS
When the 7305–14/19 is installed in a 400-type mounting assembly, it makes electrical connections to associated
equipment through a 56-pin, wire-wrap, card-edge connector, provided as part of the mounting assembly. Make
all installer connections to this connector in accordance with Table 1.
Table 1. 6305–14/19 Installer Connections
Lead Designation Pin
4W RCV STA T1
R1
5
15
2W/4W XMT STA T
R
55
49
2W/4W XMT STA SX
4W RCV STA SX
SXT
SXR
51, 53
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