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<DIV><FONT face=Arial size=2>Hi all,</FONT></DIV>
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<DIV><FONT face=Arial size=2>I was taking a look at the schematic for the music
from outer space VCO board, when I got an idea concerning a possible way to
elliminate tempcos from VCO's. I'm sure someone has probably thought of
this (like 40 years ago) but in any case, here goes... If you had a
quad of matched transistors on a single substrate (such as in the new THAT 300
series), or at least two thermally coupled pairs, couldn't you send one pair a
positive-going CV and the other pair a negative-going CV and then send the two
outputs to a differential amplifier, such that only the difference signal would
be amplified. This would elliminate the change in current with temperature
from the final output, because it would be equal in both pairs, assuming
perfectly matched and thermally-coupled devices, and the diff amp would 'ignore'
it.</FONT><FONT face=Arial size=2> Any thoughts?</FONT></DIV>
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<DIV><FONT face=Arial size=2>Dave</FONT></DIV></BODY></HTML>