[sdiy] Simple MIDI-syncable LFO...?

[Scott Gravenhorst]

This is possibly daft, but who knows, it may be appreciated.

Using the detected MIDI stream clock signal, it ought to be easy to
synch using a PLL.  If waveforms other than square or saw are required,
the PLL's VCO (4046) can be replaced with the much hated 8038 which can
then output sine or tri.  Using Thomas Henry's 8038 VCO circuit (use a
larger capacitor and voila la LFO), the 8038 will behave quite linearly
and won't heat up your house.  A proper loop filter design is required,
but I think that this method is quite usable in many if not most
situations.  The only place I can see it not working is if the piece
being played has wild tempo changes.  This method will prevent a reset
"ker-thunk" and will deliver a true analog output.



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-- Scott Gravenhorst | LegoManiac / Lego Trains / RIS 1.5
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