[sdiy] harmonic generator

[Scott Gravenhorst]

I believe that all of these except for the PLL 
are dividers of one sort or another.  Internally,
the PLL is doing division too.  Producing a divider
chain capable of all 10 lowest harmonics from one
PLL would be lots of fun too.  It might be simpler
to do it with more than one PLL.  I've gotten 4 
octave tracking out of a 4046 doing frequency 
multiplication to 12x, but as has been/will 
be mentioned, PLLs do have a portamento and/or 
hunting effect (can be minimized by optimizing 
the loop filter) and also the outputs will all be
rectangular.  

Wave shaping can do doubling easily with triangle 
waves, but non binary power harmonics?  In fact, 
all of the those methods mentioned below will be 
rectangular except the look up tables, and DAC 
games you might play with Walsh.  In these cases, 
you'll get stair stepped waves.  Filtering would 
be necessary to get sine harmonics.

What you'd need is the electronic analog of a big
gearbox that has output shafts at 1, 2, 3, 4, etc
times the input RPMs...

"John L Marshall" <john.l.marshall at gte.net> wrote:
>1. Phase Lock Loops
>2. Walsh function to sine 
>3. Divider chains
>4. Look up tables
>5. Rate multipliers
>
>John
>
>----- Original Message ----- 
>From: Rob Hukin <robh at biols.susx.ac.uk>
>To: <synth-diy at dropmix.xs4all.nl>
>Sent: Thursday, February 21, 2002 3:47 AM
>Subject: [sdiy] harmonic generator
>
>
>> Can anyone recommend a harmonic generator circuit - I need about the 
>> first 10 harmonics of a given fundamental.
>> 
>> thanks,
>> rob.
>> 
>

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