Smartphone Oscilloscope Preamp

[scimitar]

No an effects pedal I'm afraid but I thought it was worth sharing, basically allows you to safely use your smartphone or tablet as an oscilloscope (with appropriate app). For details see http://m.instructables.com/id/A-Preamplifier-for-Smartphone-Oscilloscopes/?ALLSTEPS note that this is not my instructable but I didn't want to use breadboard so decided to make my first vero layout.



As a good example of what you can do with this, I have just built the Wampler Black '65 and I wasn't sure that it was working correctly so for interest I built the schematic in LTSpice put a 1Khz sine wave through it and plotted the output (note that I had to change the bias resistors to get the voltages correct and match my build). Which gave me this graph



I then connected my phone to the preamp and probed the output of the pedal feeding it with a generated sine wave from an android tablet (with the same voltage as simulated in LTSpice) and got this output (note that because I connected the probes backwards it is inverted).



I'd call it a good match which suggests my hearing is imagining the problem.

[rocket88]

One word......AWESOME. thanks buddy.