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USER'S MANUAL
BURST OF PULSES
Burst of Pulses is a complex waveform wherein a lower
frequency waveform is used to turn on and off a higher
frequency waveform. The lower frequency is called the
cycle frequency. The higher frequency is called the burst
frequency. For example, a burst of 3 pulses at 400 Hz
with a 12% duty cycle and a 40 Hz cycle frequency would
produce the following output:
A pulse would occur every 2.5 milliseconds, (400 Hz) and
each pulse would be 0.3 milliseconds wide, (12% of the
400 Hz). After the first 3 pulses of the 400 Hz waveform
the next 7 pulses of this waveform would be skipped.
Then there would be another 3 pulses of the 400 Hz 12%
duty cycle waveform. For this waveform the bursts of
pulses occur every 25 milliseconds, (40 Hz). This pattern
would repeat as long as the switch on the anode pole was
held down. For this example, the LR-24 could not output
more than 10 pulses of the 400 Hz burst because 400 Hz
is only 10 times the cycle frequency of 40 Hz.
As a second example, if the LR-24 were set to produce
a burst of 5 pulses at 250 Hz and 10% duty cycle at a
15 Hz cycle frequency, the waveform would have these
characteristics:
A pulse would occur every 4 milliseconds, (250 Hz), each
pulse would be 0.4 milliseconds wide, (10% of the 250 Hz).
After 5 pulses of the 250 Hz waveform, the next 11 pulses
of this waveform would be skipped. Then there would be
another 5 pulses of the 250 Hz 10% duty cycle waveform.
For this waveform, the bursts of pulses occur every 67
milliseconds (15 Hz). This pattern would repeat as long
as the switch on the anode pole was held down. For this
example, the LR-24 could not put out more than 16 pulses
of the 250 Hz burst because 250 Hz is only 16.67 times the
cycle frequency of 15 Hz.
For more information on setting the burst of pulses, see
pages 16, 17, and 32.
SECTION 2: DISPLAY PANEL (CONT.)
SECTION 2