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You will be
examining the IV characteristics of the same type of
Light Emitting Diode (LED) diode as you have in your transmitter circuit.
Obtain another red LED from the parts bin.
-
Construct the circuit in Figure
on the bench-top breadboard.
Set the function generator to produce a sinusoidal,
1 kHz, 4V peak-to-peak voltage 
.
-
Set your oscilloscope for X-Y measurements, and connect the X probe to
and the Y probe to 
.
-
Analog Oscilloscope - Press the blue button labeled B-A / Sweep in so that
it is set for B-A mode. The B probe is now the Y axis and the A probe is the X axis.
-
Digital Oscilloscope - Press the Button labeled Main/Delayed. This will
cause a softkey menu to appear. Press the softkey labeled XY. Now
Probe 2 is the Y axis and probe 1 is the X axis.
-
Sketch or print-out the I-V characteristic as it appears on the screen.
-
Return the resistor and LED to the proper drawers in the parts bin.
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