[Fwd: Re: [sdiy] Oscillator sync schemes]

[cheater cheater]

How does 'burst sync' aka 'kick sync' work? How are the pulses
generated? Would that be generated by a UC?

How does PLL syncing work?

Cynthia: want to shed any light on what your new sync mode do effectively?

Personally I was considering this kind of sync scheme:

if the slave's phase is near the master's phase (+/- 0.1T for example)
then the current going into the integrator is lowered if the slave is
ahead, and raised if the slave is behind the master oscillator. How
much it is changed by, M, depends on some function, for example it
could be:

M = a*(1-10*|s-t|)^2
for 0 =< |s-t| =< 0.1

and M = 0 elsewhere.

M is the percentage of mix between the slave's current and the
master's current. If M = 100% = 1 then the slave gets the same current
as the master.

s - phase of master, [0..1]
t - phase of slave, [0..1]

a - some constant. If it is 1 then the oscillators will end up in
perfect lock. I suggest it being a small value.

There are probably better formulas for doing this, but this formula is
simple for everyone to understand the mathematics of.

Option 2:

M = a*(1-10*|s-t|)

Option 3:

M = a*(1-10*|s-t|)^k

k > 1

Option 4:

M = a*(1-10*|s-t|)^k

k > 0

Option 5:

M = a*(1-10*|s-t|)^k

k = 0

Option 6:

M = a*(1-10*|s-t|)^k

k - real number

So this is a sort of FMish thing. Note that this 'sync' works
everywhere, not only where the master's core resets. It has nothing to
do with the shunting. However you could make it work only around the
master's reset spot by windowing the value of M with another function
which assumes 1 at the zero crossing, assumes 0 at -0.1T and at 0.1T
and is linear inbetween (so called 'tent function': /\  )

Regarding the 'burst sync':

maybe the master oscillator could have a sup-octave oscillator running
at, say, f_O = 16*f_M (16xfrequency of Master)
then it could strobe every time its integrator shunts, and on that
strobe you could compare the voltages of the master and slave. Then
you could do this:

D = |s-t|^2k * (s-t) * a

Where a =<1 and k is an integer. (a > 1 could sound interesting, who knows)

You add D to the current of the slave oscillator.

So this is again FM, but it's sort of 'stochastic'. But the process is
spaced in time in such a way that it is harmonically related to the
master oscillator.

Now if you replace f_M with f_S (frequency of Slave) then you get an
alternative where the 'sync sound' is harmonically related to the
frequency of the slave. This would require the 'sup-oscillator' to
have its own integrator core, though.

D.

On Mon, Aug 17, 2009 at 8:38 PM, Cynthia Webster<cynthia.webster at gte.net> wrote:
> Chris Muir wrote:
>
>>
>> On Aug 17, 2009, at 9:29 AM, Cynthia Webster wrote:
>>
>>> The article in WikiPedia is Not Correct saying that there are only two
>>> types of sync,
>>> as there is also Variable Sync, Reset, and Variable Reset, there is also
>>> Triangle core Dual sync where it syncs twice as often at both the top and
>>> the bottom,
>>> there is also Time Reversal, and there is Core Lock.  Who the hell writes
>>> these things?
>>
>>
>> We, the people, write these things. You did correct it while you were
>> there, right?
>>
>
>
> Hi Chris!
>
> I tried but it was above the part that was editable for some reason. Maybe
> you have to be a member.
>
> Of course I understand the concept of the Wiki, but I see no name associated
> with the entry,
> so mine was more of a rhetorical question, "who writes these things"
> meaning,
> (Who thought they were qualified to write that?   I certainly didn't think I
> was, lol!)
>
> Aaron is the professor, and Paul has a fine pedigree, there are so many
> other brilliant people here
> (please don't shoot, I just just design stuff!)
>>
>> - C
>>
>> Chris Muir
>> cbm at well.com   http://www.xfade.com
>>
>>
>>
>>
>>
>>
>>
>
>
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