Figure 6-2. Typical multivibrator/integrator relationship

and Q16. This turns off alarm relay driver Q16

If the detected sound is maintained for a long period,

causing alarm relay K1 to deenergize signaling a

the 0.7 second alarm signal will repeat every 4.5

detected ultrasonic sound.

seconds, until the detected sound stops. If a loss of

power is encountered, relay K1 will de-energize and

During a state of no alarm, Q16 is conducting to a

signal an alarm. When Q16 returns to a conducting

hold relay K1 in the energized position. When the

state (no detected sound) relay K1 is again energized

alarm is activated, Q16 goes into a nonconducting

and integrator discharge Q17 is driven into conduc-

state for a period of approximately 0.7 seconds.

tion causing integrator capacity C27 to discharge.

ONE SHOT

MULTIVIBRATOR

OUTPUT

R-C

INTEGRATOR

CHARGE

VOLTAGE

SECONDS

DETAIL A - RANDOM MULTIVIBRATOR PULSING OUTPUT

ONE SHOT

MULTIVIBRATOR

OUTPUT

R-C

INTEGRATOR

CHARGE

VOLTAGE

SECONDS

DETAIL B - CONTINUOUS MULTIVIBRATOR PULSE OUTPUT

ME 6350-262-14/2/6-2

Figure 6-2. Typical multivibrator/integrator relationship

processor/transceiver ultrasonic motion signal. Op

d. Band Rejection Filter Functional Description.

eration of the processor/transceiver ultrasonic mo

The band rejection filter is used only when the

tion signal emits an ultrasonic sound at a frequency

processor/receiver ultrasonic passive signal is

of 26.3 kHz which appears within the

operating in the same environment as a

6-3