[sdiy] top octave and dividers

[jhaible at t-online.de]

Czech Martin schrieb:
> 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.

Interesting !
Does it also work the other way round, running M and N
dividers in parallel, and doing a Fast PWM switching
between the M and N diver output ? (Like "chop" vs.
"alternate" on scopes - you get the idea ...)
Would be interesting what the PD would make out of such
a signal !

JH.