®
Function Generator
Some Suggested Uses
8
Other
Current
Several displays show the root mean square (‘rms’) output current (0.00A rms). The
Function Generator calculates the true root mean square of the output current, not just
the peak current divided by the square root of two. The output current depends on the
output voltage and the resistance of the device or circuit to which the generator is con-
nected. For example, if you set the generator to output 5.00 V DC and connect the
output to a 10 ohm resistor, the output current display will show approximately 0.50A
rms. If you change to a Sine Wave, the current will read 0.707 x 0.5A = 0.35A rms.
Trigger Output
On the rear panel is a BNC connector labeled TRIGGER OUT (TTL). If you want to
trigger an oscilloscope synchronously with the generator output, just connect the
TRIGGER OUT (TTL) connector to the external trigger of the oscilloscope (cable not
included).
USB Port for Firmware Update
Next to the TRIGGER OUT (TTL) connector on the rear panel is a USB port. The
USB port allows a USB cable (not included) to be connected from a computer to the
Function Generator so that its firmware can be updated. Go to
www.pasco.com/downloads for instructions.
Some Suggested Uses
In addition to the usual uses of a function generator such as providing sine wave sig-
nals for electronics laboratories, the PI-8127 Function Generator is particular suited
for experiment in waves and acoustics.
Drive a speaker - or several speakers - with the Function Generator. Accurately set the
frequency to any level in the acoustic range or beyond. This makes it particularly con-
venient for experiments such as measuring the speed of sound, observing the interfer-
ence and diffraction of sound waves, and investigating acoustic resonance in a cavity.
Use the Function Generator with the PASCO Resonance Tube (see www.pasco.com)
to investigate resonant modes and the speed of sound in a closed or open tube.
Use the Function Generator with the PASCO Sonometer and Driver/Detector Coils to
measure resonant frequencies and harmonics and the location of nodes and antinodes
on a wire.
The built-in amplifier makes it an ideal device for driving mechanical
wave experiments. Use the generator with a PASCO Mechanical Wave
Driver to examine the resonance modes in a vibrating wave cord. Experi-
ment with the motion of waves in two dimensions by using sand on the
thin metal plates of the PASCO Chladni Plate Kit.
Use the generator with the PASCO Coupled Harmonic Oscillators to study
coupled harmonic motion of two or more gliders on an air track.
Connect the Function Generator to a resistor-capacitor (RC) circuit such
as the PASCO RLC Circuit Board and measure the voltage across the
resistor as the generator drives the circuit with a square wave.
The name “root mean square”
comes from the fact that it is the
square root of the mean of the
squares of the values.
USB Port
Voltage across the resistor in a resistor-capacitor
circuit driven by a square wave.
