[sdiy] Temperature stable lin-exp converter with a CA3086 or CA3046

[Sowa Roman]

I would avoid any designs that make heat on purpose. It's better
to compensate IMHO than to heet up.
Heat will spoil other circuits performance, degrade electro-caps
as we'we learned recently from this list, and will make you buy
bigger and bigger power supplies when your modular grow.

Roman

__-----Original Message-----
__From: Rob Mantel [mailto:rob at arachnoids.org]
__Sent: Monday, May 27, 2002 5:04 AM
__To: SynthDIYmailinglist
__Subject: [sdiy] Temperature stable lin-exp converter with a 
__CA3086 or CA3046
__
__
__Hi all,
__
__In this book I have here, they use a CA3086 (or CA3046) to 
__build a lin-exp
__convertor for a VCO. Two of the transistors inside do the real lin-exp
__conversion, two others are used to control the temperature, 
__one as 'sensor',
__one as 'heater'. From what I understand of it this should 
__lead to a constant
__temperature of the ca3086 (kind of like the old ua726 got its constant
__temperature from its oven), so no external temperature compensation is
__needed anymore.
__
__Is this a well known thing to do? If so, why doesn't everyone 
__do it this
__way, it is a very cheap solution, no expensive parts involved 
__at all. Does
__anyone have any experience with the temperature stability of 
__VCO's built
__this way?
__
__Rob (who floods the list with questions today, sorry)
__
__
__
__---------------------------------------------------------
__This message has been scanned for viruses by MIMESweeper.
__
__Wiadomosc zostala sprawdzona pod katem wirusow przez
__oprogramowanie MIMESweeper.
__


---------------------------------------------------------
This message has been scanned for viruses by MIMESweeper.

Wiadomosc zostala sprawdzona pod katem wirusow przez
oprogramowanie MIMESweeper.