I returned to DIY electronics in 2009 after a 20 year pause by building a few kits to get in shape. This blog is for me to keep track of my progress.
Digital Audio Signal Generator
This handy instrument is a version of the design published in Australian Silicon Chip (a subscription is required to view the details of the article). It is based on a dsPIC33 microcontroller, has TOSLINK and S/PDIF digital outputs (44.1k, 48k and 96k sample rates) and a stereo analog output. Output frequency, phase, attenuation, and other parameters are set by the keyboard. It produces sine, square, triangle, and sawtooth waves and has a variety of modes. It can be powered by an external DC source or a battery. The article claims low distortion for sinewave (less than .06%) and even lower with a good external DAC, but I did not have a chance to verify that just yet. Highly recommended.
Total Comments 4
Comments
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nice
is it available in kit form from Jaycar or DSE? I've been thinking about building something that does square waves, this might fit the bill nicely.
Tony.Posted 16th August 2010 at 03:08 AM by wintermute
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PCBs seem to available from RCS Radio, but I am not sure about kits - maybe it is easier for you to talk to Silicon Chip directly.
Note that any sigma-delta DAC, including the dsPIC's internal DAC that this generator uses for analog output, produces square waves with some distortion (looks like ringing).Posted 16th August 2010 at 05:56 AM by alexcp
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ok thanks for the heads up on the square wave ringing! Cheers,
Tony.Posted 16th August 2010 at 08:23 AM by wintermute
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Posted 31st October 2010 at 04:42 PM by heinz1
