-22-
Project #PC12
OBJECTIVE: To look at the output signal from an AM radio.
Build the circuit shown and
connect the PC-interface
cable to the microphone
input on your computer.
Turn on the slide switch
(snap part S1), tune the
variable capacitor (snap
part CV) to a local radio
station that gives good
reception, and set the
adjustable resistor (snap
part RV) to a comfortable
volume. The integrated
circuit (snap part U5)
detects and amplifies the
AM radio waves all around
you. The power amplifier IC
(snap part U4) drives the
speaker (snap part SP) to
complete the circuit.
In this project you will study
the audio signal at the
radio’s output to the
speaker. The actual AM
radio transmission is at
high frequencies that
cannot be viewed using
Winscope.
AM Radio PC
CI-73_REV-E_051314.qxp_CI-73_Manual_072213 5/13/14 4:01 PM Page 23
