[sdiy] BBD Chips

[René Schmitz]

Hi Jaroslaw et al,

> Yes, the clocks are independent, but there's no danger that any new
> frequencies in the
> audio range would arise.
> It's due to a fact that the output signals of all BBD's are mixed together
> in a *linear*
> summing circuit. That means, no additional sums/differences of output
> frequencies can

In an ideal world, yes. However in practice the HF (erm thats RF of 
course) can also find other ways than the signal paths. I'm not talking 
about emission, but things like power supply coupling. The clocks can 
couple there and produce mixing products in the clocking circuitry.
Been there done that. Carefully rewireing the power supply connections 
and makeing it stiff for RF helped a lot. A lesson I learned the hard way.

> clock frequency. It's the well-known Shannon theorem - also called the
> Kotielnikov
> theorem in some countries ;o)

Oh, never heared that before!

Cheers,
  René

-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159