Instruction Sheet
for the PASCO
Model WA-9318
MICROWAVE MODULATION KIT
012-02960D
12/03
SCOPE
9VDC
GUNN
MICROWAVE
MODULATOR
PASCO
scientific
Microwave
Transmitter
MODEL WA-9318
MICROWAVE
MODULATOR
FREQ
0.4 - 4 KHZ
AMPL
BIAS
DIODE
MIC
Plug in for audio input.
Unplug for triangular
wave input.
9 V Power Adapter:
Plug into 120 VAC,
60 Hz outlet.
MICROPHONE
Microwave
Receiver
Top View
Bottom View
ON
OFF
ON-OFF
Switch
Battery
Compartment
Introduction
The WA-9318 Microwave Modulation Kit turns your
PASCO Microwave Transmitter and Receiver into a
microwave communications system. Talk into the
microphone and your voice modulates the amplitude of
the transmitted microwaves, sending the signal
through space to the receiver. You can monitor the
signal at the modulator using an oscilloscope. The
signal at the receiver can also be monitored with an
oscilloscope, or you can use an audio amplifier and
speaker to provide an audible output. (The oscillo-
scope, amplifier, and speaker are not provided.)
For more quantitative investigations, the modulator
provides a triangular wave output with variable
frequency (0.4 - 4 kHz), amplitude (0 - 6 V peak-to-
peak), and bias (a DC offset to demonstrate "clip-
ping"). Using this triangular wave with an amplifier
and speaker, you can add an audible output to your
standard microwave experiments—a useful addition to
class demonstrations.
Equipment
Your WA-9318 Microwave Modulation Kit
includes (see above):
1. Microwave Modulator
*2. Microphone
3. Adapter Plugs
* Microphone: low impedance, 50-15,000 Hz fre-
quency response (replacement battery = 1.5 V
Eveready A76 or equivalent)
Adapter Plug