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SECTION 1 - INTRODUCTION
The Model AK-700 / PT-323K is a push button electronic telephone kit. Your telephone is equipped with the
following features: A) a tone/pulse switch, B) automatic redial (for pulse dialer) of up to 32 digits, C) a ringer
turn off switch, and D) four neon bulbs to give a visual indication that the telephone is ringing. The kit is built up
in three sections: 1) Ringer, 2) Transmit-Receive, and 3) Dialer. As each section is added, its function is
explained and tests are run to demonstrate its operation.
FCC regulations do not allow the Model AK-700 / PT-323K Telephone to be connected to the telephone network
unless it has been either assembled under the supervision of an instructor or been tested by Elenco
®
.
SECTION 2 - FCC REQUIREMENTS
For the last several years, the Federal Communications Commission (FCC) has provided the standards for the
protection of the telephone network from harm caused by the connection of terminal equipment. The rules
established require that all terminal equipment, such as your telephone, be registered with the FCC. The FCC
registration number of your telephone is GXA3PP-19545-TE-E.
If trouble is experienced, the telephone must be removed from the telephone network to determine if it is
malfunctioning. If it is malfunctioning, the telephone must not be reconnected to the telephone network until
repairs are made. Repairs should be made by Elenco
®
. To arrange for repairs, contact Elenco
®
at the address
given on the back of this manual.
SECTION 3 - GENERAL DESCRIPTION
The primary purpose of the telephone is to transmit and receive voice signals allowing two people with
telephones to communicate with each other. To be of practical value, the telephone must be connected to a
switching network capable of connecting each telephone to many other telephones. To accomplish this switching,
each subscriber telephone is connected to the telephone company's Central Office by two wires referred to as
the "Local Loop". A simplified diagram of this connection is shown in Figure 3-1. The Tip and Ring designation
of the + and – leads come from the days of the manual switchboard. The tip of the plug the operator used to
connect telephones carried the (+) lead and the ring immediately behind the tip carried the (–) lead.
When a subscriber wishes to place a call, they merely pick up the telephone and a small current flows in the
local loop. This current picks a relay in the Central Office indicating that service is being requested. When the
Central Office is ready to accept the number being called, a dial tone is sent to the calling telephone. The dial
pulses, or tones, then signal to the Central Office the number of the telephone being called. A path is then
established to that telephone. This path may be a simple wire connection to a telephone connected to the same
Central Office or it may go via wire, microwave link, or satellite to a telephone connected to a distant Central
Office. To signal the incoming call, a ringing signal is placed on the local loop of the called telephone. The
ringing signal is a 90 VAC 20Hz signal superimposed on the 48VDC present on the local loop. A ringing tone
is also sent to the calling telephone. When the called party picks up the telephone, voice communication is
established.
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