Operation - AT&T Bell System 401E Series Description And Operation

SECT ION 594-014- 100
Fig. 3-Data Set 401 E-Type-Rear V iew
3.06
Data sets 401E3 and 401E5 (Fig. 4) differ
from other data sets 401E-type (Fig. 5) as
follows:
• Answer-back signals and data signals are
coupled directly to the telephone network
through a capacitor for monitoring by the
telephone handset.
• Contacts of the data key remove the transmitter
of the telephone from the circuit and connect
the voice answer-back CP3 circuit pack.
• The oscillators are modified to enable the
handset to be used for monitoring .
3.07
• Data set 401E2 or 401E4 transmitters can
be used as a replacement for data set
401A -type transmitters to work with data set
403-type receivers. This is accomplished by installing
option M on data set 401E2 or 401E4 . If option
M has been installed, the label OPTION M will
Page 4
have been placed above the customer interface
connector at the rear of the data set.
No te: Data set 401E-type transmitters can
be used as a replacement for data set 401A-type
transmitters to work with data set 401J-type
receivers with no modification required .•
4. OPERATION
4.01
The data key is located on the switchhook
assembly in the same position as ~n exclusion
key . Functions of the key are as follows:
Key in Normal Position ( Down )
• Connects telephone circuit to line.
• Connects extension telephone and speakerphone
leads to line.
• Removes data transmitter from line.