TM 11-5805-689-14
THEORY AND OPERATION
provide tones to operate the central office automatic
switchboard. Each channel is terminated through a
The CV-1919/G is a three-channel transistorized
four-wire trunk connection to the central office
two/four-wire telephone signal converter designed to
automatic
switchboard.
This
Converter
function in conjunction with the Tactical Automatic
automatically accepts calls from the central office
Switching (TAS) Network. The Converter has been
automatic switchboard and
alerts the two-wire
designed to comply with the Electronics Command
manual switchboard operator when a request-for-
Technical Requirement SCL-4659C and associated
service has been made. The manual switchboard
amendments. Power for this Converter is provided
operator responds to the request-for-service by
by a battery of four "D" size energy cells (in series
inserting a cord-plug from the manual switchboard
connection) to supply a nominal 6.4 volts with fresh
into the jack of the channel displaying the request-
cells and a minimum of 4.4 volts at cell life end. The
for-service (flag) and then momentarily depresses
Converter circuitry has been designed to provide a
the ACCESS pushbutton of that channel. These
minimum of 20 hours continuous service (from in-
actions by the manuaI switchboard operator reset
stallation of fresh cells to, their end of life) in an
the SRI, stop signals being sent by the Converter at
vironment of 0F temperature with a calling rate of
the central office automatic switchboard and opens
100 three-minute calls per 24 hour period when 50
the voice path between the manual switchboard
percent of the calls require use of the keysender. The
operator and the central office. The two-wire con-
Converter is designed to interface telephone signals
nection is made by the manual switchboard operator
between an automatic analog four-wire central office,
inserting the cord-plug from the two-wire position on
AN/TTC-25 and manual two-wire telephone switch-
the manual switchboard which is being called or is
boards, SB-86()/P and SB-22()/PT. This Con-
requesting service to a four-wire trunk. With these
verter is used in conjunction with the manual two-
provisions this Converter may interface three in-
wire switchboard to interface any two-wire telephone
dividual two-wire trunk connections to three four-
connection made by plug and jack with any four-wire
wire trunk connections at any one time. The elec-
trunk connection between this Converter and a
tronic processing of a call from the automatic
central office automatic switchboard AN/TTC-25.
switching center will be described in the following
The CV-1919/G Converter contains three modular
paragraphs. Functional block diagram is included
interfacing channels and common equipment to