[sdiy] Cheapest Matched Pair

[patchell]

    I used Terry's design, and I would say that because there are no real signals
on the expo transistors, this probably does a lot to keep the cross coupling
down.  Also, I do have a LOT of bypass caps...

ijfritz at earthlink.net wrote:

> I wonder if this wouldn't depend on the design used for the oscillator core.
> For example, a SAW VCO where the integrating cap is connected directly to the
> converter will produce a large rapid voltage swing at the converter output,
> but one where an op amp integrator is used (Terry's design) has the converter
> driving a virtual ground, so the output voltage of the converter is fixed.
>
> In addition, it's easy to end up with switching transients being coupled into
> the converter indirectly if proper decoupling techniques are not used. In this
> case syncing could occur whether the transistors are in the same package or
> not.
>
>   Ian
>
> On Mon, 30 Dec 2002 12:23:38 -0800 patchell <patchell at silcom.com> wrote:
>
> >     I can double that.  I made some dual VCO's
> > from MAT-04's and had no problems with
> > soft syncing either.
> >
> > harrybissell wrote:
> >
> > > Hmmm... i wonder.
> > >
> > > I have never tried the 3046 for a dual VCO...
> > >
> > > but I have used the MAT-04 and had no soft
> > syncing
> > > problems.

--
 -Jim
------------------------------------------------
* Visit:http://www.silcom.com/~patchell/
*-----------------------------------------------
*I'm sure glad Merry Christmas comes just once a year
* -Yogi Yorgensen
------------------------------------------------