Manual

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T
his circuit is what engineers refer to as a “pulse
oscillator”. It will make machine gun like sounds.
There are many different ways to make oscillators.
In this kit, you will build several of them and later on,
you will be told on how they work. In the meantime,
we will just tell you what an oscillator is.
An oscillator is a circuit that goes from high to low
output on its own, or in other words, it turns itself on
and off. A pulse oscillator is controlled from pulses,
like the pulses made from a capacitor charging and
discharging. The oscillator in this kit turns off and on
slowly. However, some oscillators turn off and on
many thousands of times per second. Slower
oscillators can often be seen controlling blinking
lights, such as turn signals in a car or truck. “Fast”
oscillators are used to produce sound. The fastest
oscillators produce radio frequency signals known
as “RF signals”. The RF signal oscillators turn on
and off millions of times per second!
The amount of times an oscillator turns off and on
each second is called the frequency of the oscillator.
Frequency is measured in units called hertz (Hz).
The frequency of this oscillator is about 1 to 12Hz.
The frequency of a radio signal oscillator would be
measured in either MHz (megahertz, meaning a
million hertz) or kHz (kilohertz, meaning a thousand
hertz).
O
nce you finish wiring, press the key to start the
oscillator. The 50kW resistor is the control; you can
s
wap it out with other resistors to change the sound
f
rom a few pulses per second to a dozen or so per
second. Also, you can change the frequency of this
oscillator circuit by swapping out other capacitors in
place of the 10mF. Remember to observe the correct
polarity!
Notes:
EXPERIMENT #11: MACHINE GUN OSCILLATOR
Wiring Sequence:
o 1-29
o 2-30
o 3-110-114
o 4-27-138
o 5-41-109
o 28-82
o 40-113-81
o 42-119
o 121-122
o 124-137
Schematic
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