LOADING HEADSET-CHESTSETS.-- Sound-
powered telephone headset-chestsets are designed to
operate with 10 sets in parallel without any noticeable
effect in response. However, it is possible to parallel up
to 20 sets before overall line level response is considered
critical. To maintain the overall efficiency of the circuit,
do not tape down the transmitter button for convenience,
as this may overload the circuit. When using the
headset-chestset, hold the press-to-talk switch down
firmly to ensure good contact, and talk directly into the
transmitter. When listening, be sure to release the
press-to-talk switch to eliminate the pickup of
extraneous sounds and also the loss in receiver signal
strength due to the low impedance transmitter shunted
across the line.
REMOVING HEADSET-CHESTSETS.-- When
removing a sound-powered telephone headset-chestset,
you should use the following proceedure:
1. Remove the headband and hang it over the yoke
of the transmitter.
2. Remove the plug from the jackbox and replace
the jack cover on the jackbox to keep out moisture and
3. Lay the cord out on the deck and remove any
Figure 5-12.--A properly made-up sound-powered telephone
4. Coil up the cord, starting from the end that
attaches to the chestplate. Coil with the right hand,
making the loops in a clockwise direction. The loops
should stow these sets in stowage boxes, which are
should be about 10 inches across.
designed for stowing one set or up to six sets.
5. After the cord is coiled, remove the headband
A properly made-up set should fit into its stowage
from the transmitter yoke and hold the headband in the
box without forcing. Never allow a loose cord to hang
same hand with the cord.
out of the box because it maybe damaged when the lid
6. Fold the transmitter yoke flat so that the
is closed. Never use the stowage box for storing cleaning
mouthpiece lays flush against the chestplate connection
gear or tools because rags give off moisture and soap
box, using care not to pinch the transmitter cord.
powder gives off fumes that will cause the aluminum
diaphragms to rapidly oxidize. Tools and other loose
7. Hold the headband and cord in the left hand and
gear may damage the set(s) or may prevent you from
unhook one end of the neck strap from the chestplate.
getting a set out quickly in an emergency situation.
8. Bring the top of the chestplate level with the
headband and cord. Secure the chestplate in this position
by winding the neck strap around the headband and
Sound-Powered Telephone Maintenance
coiled cord just enough times so that there will be a short
end left over. Twist this end once and refasten it to the
As an IC Electrician, you will be required to service
chestplate. The set is now made up and ready for
sound-powered telephones. Because a great deal of time
stowing, Figure 5-12 shows a properly made up
is devoted to the repair of these sets, you should become
sound-powered telephone headset-chestset.
thoroughly familiar with the proper methods of testing
STOWING HEADSET-CHESTSETS.-- In
and repairing them. Many of the larger ships in the fleet
have a telephone shop devoted entirely to the repair of
enclosed spaces, you should stow headset-chestsets on
hooks. In machinery spaces and on weather decks, you