TM
3-6665-316-12
TECHNICAL
THEORY OF OPERATION (continued)
1-13.
Each Simulator includes two sets of
tone modules.
One
set is
known
as
the
standard
set, and the other set is known as
the special-purpose
set.
Every tone module in a standard set has a GROUP number 000. Every standard set is
That is, the tone modules in all standard sets contain the same resistors
the same.
Every tone module with SERIAL number 000-4, for
arranged in the same sequences.
example, is the same as every other tone module with that SERIAL number.
Special-purpose tone module sets have GROUP numbers other than 000. Receivers
containing tone modules from a special-purpose set will respond only to a transmit-
ter containing a tone module from the same set.
A transmitter is powered by batteries which are mounted in the unit.
Power is
routed to the encoder printed wiring assembly when the OPR switch is pushed to OPR
A built-in test circuit monitors
and the CHAN SEL switch is set to 1, 2, 3, or 4.
battery voltage, and causes the TEST GOOD indicator to light if the batteries are
At the same time, a signal is transmitted.
good .
If the
OPR switch is pushed to the OPR position while the CHAN SEL switch is set to
TEST,
power is routed to a dummy load which simulates the transmitter-circuitry
load.
If the batteries are good, the TEST GOOD indicator comes on.
No signal is
broadc
ast.
Batteries
which
test
GOOD
assure
that
the
transmitter
can
broadcast
a
signal
1000
meters.
Receivers are installed in, and draw operating power from, the host detectors.
Every decoder printed wiring assembly includes a voltage regulator. Therefore, the
receiver can be operated whenever power within the correct range (+18 to +36 V) is
The receiver requires a nominal +12 V.
connected to the detector.
A M43Al Interface Cable is used to connect receiver and detector circuitry when a
receiver is installed in a M43A1 Detector.
This cable attaches to a test connector
on the detector.
Power and necessary signals travel between the detector and the
receiver through this cable.
When a correctly coded transmitter signal is picked
up, a relay in the decoder printed wiring assembly closes.
This closure routes an
electrical ground to the detector circuitry through the interface cable.
The
ground triggers the built-in-test (BIT) circuit, causing `the detector to alarm.
1-18
