AW: [sdiy] top octave and dividers

[Czech Martin]

Yes, this idea stems from HAM radio also.
Because you need a few Hz acuracy, this would mean very low
frequency after the pll divider (or divider increment).
This in turn will make the loop filter requirements slow,
this will then make the pll slow und thus introduce phase
noise.

Instead it was chosen to divide a couple of times by N,
and then by M, thus giving fractional scaling.


m.c.

> -----Ursprüngliche Nachricht-----
> Von: jhaible at t-online.de [mailto:jhaible at t-online.de]
> Gesendet: Montag, 26. November 2001 12:34
> An: Czech Martin
> Cc: diy (E-Mail)
> Betreff: Re: [sdiy] top octave and dividers
> 
> 
> 
> > I also have an article about noninteger division (i.e. 
> > time multiplexed 
> > divider ratios) for plls.
> 
> Great idea ! 
> And the PLL's loop filter will smooth most of the jitter
> from switching divider ratios ?
> The VCO cannot really be locked then, but it wouldn't matter.
> 
> If this works, you can also adjust the scale with a CV by
> changing the "puls width" of the divider ratio multiplexing ...
> 
> JH.
>