[sdiy] Fw: Reference stabilizes exponential current

[Jim Patchell]

    Sort of my mistake.  At the top of the page, in large print, it says:
"Edited by Bill Travis"

    And below that, in smaller print it says:

    Tom Napier, North Wales, PA

    Without my glasses, I could plainly see the Bill Travis name, well, actually
even with my glasses...but, like a true American, I will blame this mistake on
EDN rather on myself for not carefully reading the attribution... :-)

    -Jim

harry bissell wrote:

> BILL TRAVIS circuit ???
>
> This is a problem. The circuit was by Tom Napier,
> North Wales, PA.
>
> Bill Travis (while a good enough guy) is an
> EDITOR at EDN, not the designer.
>
> I did not see the online version but if you did...
> and it attributes this design idea to Bill Travis...
>
> PLEASE contact EDN immediatly and request they publish
> a correction (because its wrong) and an APOLOGY...
>
> because this is not the first time they've done this.
> I have contected them in the past. They should KNOW by
> now...
>
> H^(  harry   (un-Happy)
>
> --- Jim Patchell <patchell at silcom.com> wrote:
> >     What he did is not all that different from
> > experments that I have done, as
> > well as JH did.  The output of IC3 is proportional
> > to temperature, and can be
> > used to control the gain of the expo driver.  The
> > methodes that JH and myself
> > use don't require an extra transistor in expo array
> > so that they could be used
> > with just matched pairs.  However, I have to say, if
> > you are going to be using a
> > DAC to set the pitch of your VCO, the Bill Travis
> > circuit does have a certain
> > apeal.
> >
> > Craig Critchley wrote:
> >
> > > The author of this article must be a nut for
> > different ways to build an
> > > exponential converter.  I thought the name looked
> > familiar from a recent
> > > Circuit Cellar article, from the September issue,
> > and sure enough the name's
> > > the same.
> > >
> > > In the Circuit Cellar article, he uses two
> > additional transistors in a
> > > ca3046 to heat the chip to a constant temperature.
> >  In that article it was
> > > driving a 74hct4046 vco.  He claimed 4 decades of
> > accuracy for it.
> > >
> > > It doesn't look like this article is online yet,
> > but the Circuit Cellar
> > > archive only goes up to Aug. so maybe it will be
> > available later.
> > >
> > >                             ...Craig
> > >
> > > ----- Original Message -----
> > > From: "Michael Lloyd" <mlloyd1 at enteract.com>
> > > To: <synth-diy at dropmix.xs4all.nl>
> > > Sent: Wednesday, October 31, 2001 6:20 PM
> > > Subject: [sdiy] Fw: Reference stabilizes
> > exponential current
> > >
> > > ----- Original Message -----
> > > From: Michael Lloyd
> > > To: mlloyd
> > > Sent: Wednesday, October 31, 2001 2:59 PM
> > > Subject: Reference stabilizes exponential current
> > >
> > >
> >
> http://www.e-insite.net/ednmag/index.asp?layout=article&stt=000&articleid=CA
> > > 178103&pubdate=10/25/2001
> >
> >
> >
>
> __________________________________________________
> Do You Yahoo!?
> Make a great connection at Yahoo! Personals.
> http://personals.yahoo.com