Common Telephone `lkoubles

the cover. Lift the transmission network off the

relief bushing in the cord hole, and connect the

threaded studs. Position the new transmission network

terminal wires to the terminal board.

on the studs and secure it to the cover. Connect the 17

Dial.-- To replace a dial, remove the telephone set

lead terminals to the network. Reconnect the terminal

from its enclosure and disconnect the terminal wires

wires to the terminal board and secure the telephone

from the terminal board. Remove the telephone set

set in its enclosure.

chassis from the telephone set cover. Remove the

screws that hold the dial to the chassis, lift the dial out

Common Telephone `lkoubles

of the chassis, and remove the dial dust cover.

Disconnect the four leads from the screw terminals of

Some of the more common telephone set troubles

the dial.

include (1) no dial tone, (2) dial impulses heard in the

Connect the four leads to the new dial, and secure

receiver while dialing, (3) poor transmission quality,

the dust cover on the dial. Insert the new dial in the

(4) low reception, (5) can transmit but cannot receive,

chassis, and secure the dial to the chassis. Secure the

(6) can receive but cannot transmit, (7) ringer does not

sound, (8) telephone set consistently dials the wrong

chassis on the telephone set cover, and reassemble the

number, (9) noisy connection, and (10) sidetone too

telephone set for normal operation.

loud. Procedures for analyzing these troubles and the

Ringer.-- To replace a ringer, remove the tele-

corrective actions you should take if they occur are

phone set from its enclosure and disconnect the

discussed briefly in the following paragraphs.

terminal wires from the terminal board. Remove the

NO DIAL TONE.-- If no dial tone is present, you

telephone set chassis from the telephone set cover.

must determine whether the telephone set, telephone

Unsolder the red lead and the green lead from the

line, or automatic dial telephone switchboard is the

ringer terminals. Remove the screws that hold the

cause of the problem. To isolate the problem, connect

ringer to the chassis and lift the ringer off the chassis.

a hand test telephone across the line. If a dial tone is

Mount the new ringer on the chassis and secure

present using the hand test telephone, then the problem

the ringer to the chassis. Solder the red lead and the

is in the telephone set. If the problem is in the set, it

green lead to the ringer. Secure the chassis on the

could be in the hookswitch, the receiver, the handset

telephone set cover and reassemble the telephone set

or desk set cord, or the transmission network. Once you

for normal operation.

isolate the problem, replace the defective component.

Dial Illumination Lamp.-- To replace the dial

If a dial tone is not present when checking the line

illumination lamp, remove the telephone set from its

with the hand test telephone, then the problem is either

enclosure. Remove the screw that secures the lamp

an open in the telephone line coming from the

holder to the chassis. Lift the lamp holder up until the

automatic dial telephone switchboard or in the

lamp is clear of the grommet, and then turn the lamp

switchboard itself. If the problem is found in the

holder over. Remove the lamp from the lamp holder

switchboard, you will need to refer to the switchboard

by pressing the lamp down gently and rotating it

technical manual.

counterclockwise approximately one-quarter turn.

DIAL PULSES HEARD WHILE DIALING.--

Install the new lamp in the lamp holder by pressing

Dial pulses heard in the receiver while you are dialing

the lamp down gently and rotating it clockwise

are usually the result of the hookswitch shunt spring

approximately one-quarter turn. Turn the lamp holder

contacts being out of adjustment. The contacts should

over and insert the new lamp in the grommet. Press

make when dialing. If the hookswitch contacts are

down until the lamp holder is against the grommet.

working properly, check the transmission network. If

Secure the lamp holder to the chassis. Remove the

there is a problem with the transmission network,

handset from its holder and check to see that the lamp

replace it. If the contacts are out of adjustment, adjust

lights.

the contacts by bending them.

Transmission Network. -- To replace the

POOR TRANSMISSION QUALITY.-- If a

transmission network, remove the telephone set from

telephone transmits poorly, the fault is probably in the

its enclosure and disconnect the terminal wires from

transmitter unit. One cause could be the carbon

the terminal board. Remove the 17 lead terminals from

granules inside the transmitter clinging together. You

the transmission network. Remove the two nuts and

can try and loosen the carbon granules in the

lockwashers that secure the transmission network to

transmitter by holding the handset in a horizontal

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