SECTION I - BASIC SYSTEM
Model 80K
USED WITH ALL MODELS
Containing electronic components for generating
sounds, the Model 80K amplifier is the basic part
of the siren and common to all models described in
this Manual. It will be found in the same cabinet
with it’s controls or in a separate cabinet remote
from it’s controls.
External Components Include:
a) Park Kill Wire- deactivates siren when
grounded.
b) Power Transistors (Rear) - Electrically
“hot” during Siren/P.A. operation. Contact
with metal objects will destroy them.
c) Fuse (Rear) - In unlikely event of failure,
do not overfuse.
PRECAUTIONS
1. Although the 80K has an extremely wide operating
temperature range (-40F to + 185F), underhood
installation where temperatures exceed 230F is not
advised.
2. Cabinet is not waterproof.
BLOW-OUT PROOF TRANSISTOR PROTECTION
1. Output transistors, blown out in normal sirens by
failures of the siren speaker or its wiring are protected
in the Unitrol 80K by automatic circuitry.
a) Short-circuited speaker or wiring stops
siren sounds. A soft “popping” noise from
the speaker or amplifier will occur 60 times
per minute.
b) Blown-out speaker (open coil) or
disconnected speaker wire causes amplifier
to emit siren sounds from amplifier but not
from speaker.
c) Primary input voltage above 16Vdc will
cause shutdown of tone generating stages. No
sounds will be emitted by the amplifier or siren
speaker.
2. In all instances, amplifier operation will automatically
resume when the external defect is repaired.
ASSEMBLY METHODS
1. Amplifier can be used with control units as
follows:
a) Remote - Amplifier is installed
remotely from control unit and
connected by a 4 foot or 15 foot
cable.
b) Single-Unit - Amplifier / control
unit are plugged together and
housed in one cabinet.
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