Push Button Magneto Telephone

This Push Button Magneto Telephone is similar to the Rotating Type Magneto Telephone, but the Ring Generator is Electronic and appears across the Lines as along as the ‘Press To Call’ (PTC) button is pressed.
It works on 6VDC supply from 6V, 1.2 AH Ni-Mh Battery provided inside and a charger working on 100 - 300VAC, 50 Hz. Provision is given in the Rosette Box to connect external 6VDC

SCOPE :
The Push Button Magneto Telephone Model MTI 201 is used for Point to Point Communication for a distance of 10 Kms., when the diameter of copper conductor is 1.5 mm Sq.
CONSTRUCTION :
The Telephone is Desk Type, housed in ABS (Acrylonitrile Butadiene Styrene) Plastic Moulded Body (Cover and Base) and Handset.
It has Electro Dynamic Transducers for Transmitter and Receiver.
It has Coiled Cord and Straight Cord, a Rosette Box for connecting Line and external Power Supply (if required).
The Ring Generator, Ringer, Induction Coil and other Speech Circuitry are wired in a PCB of 1.6mm thick FRP Printed Circuit Board. A standard hook (Cradle) Switch provided disconnects the incoming Ringing Voltage when lifted. To call the handset has to be on the hook.
A Press to Call (PTC) Switch is provided on the top for Calling and a Press to Talk (PTT) Switch is provided in the handset.
TECHNICAL :
(1) Ring Generator :
Frequency : 25 ± 5Hz
Output : 60VAC max.
(2) Speech :
Tx : 0dB across Lines
Rx : -12dB
POWER SUPPLY :
The Telephone works on 6V DC supply from a 6V, 1.2 AH Ni-MH Battery provided inside.
A Socket is provided at the back of the Telephone Body to connect a charger working on 100-300VAC, 50Hz. A hinged metal door is provided on the top of the Telephone to replace the Battery as and when required. The external voltage connection provided in the Rosette Box can accept a maximum of 6V DC only.
CONSUMPTION :
Idle : 3mA
Conversation : 15mA
Ringing : 300mA
INSTALLATION
(1) Open the Rosette Box and connect L1, L2 between one phone and the other.
(2) Open the cover of each Battery Box on top cover and slide on ‘ON’ the Switch provided inside the compartment.
(3) The Power ON LED shall glow. Replace the cover.
(4) Press the Call Button and ensure that the other phone is ringing. All this time, the calling handset has to be on the hook.
(5) The Charger can be connected as and when the Battery Voltage is low. The Charger has a LED which goes off when the Battery is fully Charged.