[sdiy] VCO saw integrator cap questions

[David G. Dixon]

Ian, thank you, thank you!  And thanks to Kevin and Oscar for links to great
info, as well.  The Bissell dissertation is especially useful; I don't know
how I missed it, or perhaps I saw it many months ago and wasn't ready to
make use of the information.  Either way, very helpful!

Just being able to use C0G for everything (small) will make life (and board
layouts) oh so much easier!

> At 12:21 AM 9/21/2009, David G. Dixon wrote:
> >What about C0G monolithic ceramics?  They are
> >supposed to be extremely stable with temperature.  Why don't we use them
> for
> >VCOs?
> 
> Those are what I use now, as I've mentioned here several times.  I've
> compared them against polystyrene is several designs and they work just as
> well.  Additionally, one occassionally runs into bad polystyrenes, and
> they
> are easy to damage with heat, which has given a number of builders
> problems.
> 
> 
> >3) I get ceramic caps from my school, and they are these pretty little
> blue
> >things, some only about 3 mm wide and maybe 1.5 mm thick, with white
> >markings (I think they're EPCOS, supplied by Digikey).  They are C0G in
> >smaller values (up to 2n2), and typically have 0.1" lead spacing,
> although
> >some are 0.2".
> 
> Yes, those are the ones.  Just put them in marked containers when you get
> them you will always know they are C0G.  They are small because of their
> multilayer construction and relatively low voltage rating.
> 
> 
> >I use them for coupling, bypassing, and speed-up
> >applications, but never for timing (integrators, filters, etc).  Could I?
> >Should I?  They seem to work perfectly well.
> 
> Yes you could/should.  Yes, yes.
> 
> Ian