[sdiy] New Thomas Henry VCO-1 Page Up

[Ian Fritz]

At 01:18 PM 5/27/2007, Neil Johnson wrote:

>It is a continual source of amazement to me that so much effort and
>expense is put into the choice of fast comparators, low-offset
>opamps, esoteric temperature compensation schemes, etc, only for the
>design to then rely on the supply rails for reference or other
>critical voltages.  Especially given the low cost and ease of use of
>even half-decent bandgap reference diodes available these days.

Agreed.  But for a retrofit it's much easier to pop in new parts than it is 
to redo supply lines, add extra regulators, etc.  Also one can improve 
tracking by parts substitution, which is useful in itself, IMO.  And, since 
I did my T compensation in situ, PS drift is at least partially 
compensated.  But if I were redoing from scratch it would look different!

   Ian