Equipment list:
Dual trace scope
HP function generator
HP-DMM
Pasco frequency counters
BNC T connector
2 BNC to BNC cables
1 BNC to banana
Background:
How do you know you are reading your scope voltages and periods with
accuracy?
Your instructor could tell you but then, you'd have to find him! So
being
on your own, you need to measure the function generator's output by
more
than one method and then compare. The instrument you will use to verify
your
period measurements is a frequency counter. A frequency counter
provides
a digital output of the frequency of the signal you are measuring.
Connect
the frequency counter to the "sync" output on your function generator.
The
sync BNC jack is specifically designed to be connected to a frequency
counter.
The HP-DMM is designed to measure an AC signal by representing it as an
average
value, the "RMS" value (root-mean-square). There is a conversion factor
allowing
you to convert from peak to peak voltage to RMS voltage. That
conversion
depends on the type of waveform being measured. See your instructor for
those
derivations.
Procedure:
Calibrate your scope to its calibration signal and verify that your
scope
and leads are working properly.
Your function generator has an output of three different waveforms,
sinusoid,
triangle, and square. For each different waveform, test two different
signals
(different in peak-to-peak voltage and frequency) for a total of six
different
signals. Your scope measurements should be within five percent of the
meter
readings from the HP-DMM and frequency counter (less than one percent
is
very good and not uncommon). Your HP-DMM has difficulty sampling
frequencies
over about 100 kilohertz, so stay well below those values or its
reading
will be highly inaccurate.
Conclusion:
So how close did you get?