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BLUESHIFT CHORUS / BOSS DC-2 DIMENSION C
2. Set the signal generator to output an 8 kHz sine wave at 2V peak-to-peak. Feed this signal into the pad
marked “A” (circuit input), taking care to connect the signal generator’s ground wire to a common ground.
3. Connect the oscilloscope probe to the pad marked TP1, taking care to connect the ground wire of the
probe to a common ground.
4. Adjust TR1 until the positive and negative halves of the waveforms are symmetrical. They will not be a
pure sine wave like the input, but they should be rounded off in about the same shape as each other.
5. Repeat this process with TP2 and TR2.
What type of oscilloscope should you use?
I use and recommend the
, a relatively inexpensive (USD $230) software-based
oscilloscope that also includes signal generation functionality. The hardware connects via USB, and you can
use a computer, smartphone or tablet to control it and view the display output. I haven’t used it extensively, but
it has gotten excellent reviews from others and definitely did what I needed it to for this project. There are a few
tutorials and videos available online if you want to see more about it.
What should the waveform look like?
Here is a sample waveform taken from a test point on a real DC-2 unit. This is a screenshot from the
LabNation SmartScope software. The voltage range is set to 1V and the timebase range is set to 50μs. Notice
that the waveforms are symmetrical between top and bottom, but that they are not a perfect sine wave. They
are ever-so-slightly lopsided toward the right side of the wave.
