Phoenix Analog Companion Box
Most of the experiments require analog
circuits to interface the sensor outputs to the digitizer inputs.
To implement them, we need some regulated power supplies and good
operational amplifiers. Sine wave generators are also required
for many experiments. The Phoenix Analog Companion Box packs these
thing in a 7" x 6" x 2" box.
Hardware Features:
- +/- 12V / 100 mA regulated DC output
- 3-0-3 Volts AC outputs, to study rectifier,
multipliers etc.
- 4 amplifiers implemented using OP27 op-amps
(offset is 30 uV)
- Sine wave generator with amplitude and
frequency
control (100 Hz to 300 Hz)
- Sine wave generator with AM,
FM options (3.5 KHz to 8 KHz)
Here is a Photograph and circuit schematic
It is possible to do experiments in amplitude and frequency
modulation using this accessory. Software allows to fit the output
using the equation of a sinusoid or take a Fourier transform of it. The
Python program 'fit_sine.py'
captures the output wave form, fed to CH0 through the level shifter,
and calculates its frequency using the curve fitting technique.