UNISource Corporation FG-8102, Руководство по эксплуатации

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2) Considerations
A. When generating ramp waves or skewed sine waves, it may be easier to
measure the time periods on oscilloscope using the square wave mode, then
switch to the desired operating mode.
B. For ease and accuracy in measurement, use a higher sweep speed on the
oscilloscope to expand the pulse width for measurement, then reduce sweep
speed to measure the repetition rate.
C. Repetition rate may be expressed as a frequency or time period. Measure
the repetition rate as a time period on oscilloscope and convert to frequency
if required. The repetition rate includes the full cycle, both the pulse width
and rest time for pulses, the rise time and fall time for ramp waves.
D. Repetition rate can be measured accurately and easily as a frequency or
time period with a frequency counter.
E. Pulse width also can be measured on a frequency counter, but only with the
SYMMETRY control set off before the pulse waveform is “stretched”. Pulse
width equals one-half the time period of the square wave. If the counter is
not equipped for period measurement, calculate the frequency, which is
equivalent to the desired pulse width, and measure the frequency of the
waveform.
1
DESIRED PULSE WIDTH x 2
3-5-1. TTL/CMOS OUTPUT(FG-8102/FG-8103 only)
TTL/CMOS output is specifically designed for compatibility with TTL/CMOS digital
logic circuits. Set-up time is considerably reduced because the fixed logic levels
and polarity are ready for direct injection into TTL/CMOS circuits. there is a need
for protection from accidental Application of too high amplitude or incorrect DC
offset which might damage semiconductors. Another advantage is the extremely
fast rise time and fall time of signal. To use the TTL/CMOS output, connect a cable
from TTL/CMOS BNC on the Front panel to the point at which it is desired to inject
the signal. TL/CMOS output may be used in several modes of operation. Some
examples follow.
DESIRED FREQUENCY =