Manual

-87-
T
his circuit has a multivibrator connected to a pulse
type oscillator. Rather than turning the oscillator
completely on and off, the multivibrator provides a
t
remolo effect (a wavering tone).
After you build the circuit, use the control to vary the
base current supplied to the NPN transistor. This
changes the charge/discharge rate of the 0.1mF and
0.05mF capacitors, as well the frequency of the
pulse oscillator.
The key works to turn the whole circuit on and off.
You can substitute it with the slide switch. By
changing the 10mF and 3.3mF capacitor values, you
can change the tonal range.
Try using the switch or the key to add additional
components to the circuit (like an extra capacitor in
parallel with the 10mF or 3.3mF), so you can alter
from one tonal range to another, quickly. These
changes will make a more complete organ from this
experiment. Be sure to make notes on what you do.
N
otes:
EXPERIMENT #69: ELECTRONIC ORGAN OSCILLATOR
Wiring Sequence:
o 1-29
o 2-30
o 3-47-106
o 4-74-45-42-119
o 5-105-109
o 27-46-110
o 28-86
o 40-111-80
o 41-114-78
o 43-113-82
o 44-112-87-76
o 77-75-81-79-48-138
o 73-85-88
o 120-137
Schematic
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