Re: New Vector Monitor Project: DEFLECTION SCHEMATIC FOR REVIEW

----- Original Message -----
From: James Nelson <nelsonjjjj@didactics.com>
To: <vectorlist@lists.cc.utexas.edu>
Sent: Wednesday, November 03, 1999 6:36 AM
Subject: Re: New Vector Monitor Project: DEFLECTION SCHEMATIC FOR REVIEW

> Excellent comments! (be as hard on me as you can) This is a technical
> discussion.
> Some of the issues I was planning to address with more protection
circuitry.
> I will address each issue mentioned and drop another schematic.
> By the way, Op Amps don't blow up and aren't even taxed when they go full
> rail
>
> Thanks,
> James
>
> ----- Original Message -----
> From: Rodger Boots <rlboots@cedar-rapids.net>
> To: <vectorlist@lists.cc.utexas.edu>
> Sent: Wednesday, November 03, 1999 4:58 AM
> Subject: Re: New Vector Monitor Project: DEFLECTION SCHEMATIC FOR REVIEW
>
>
> > Well, it IS a try, but it needs more work. Here's where you went wrong.
> >
> > First thing is the opamp running from + and - 15 volts, but the output
of
> > the opamp has to be able to swing to the negative rail of the output
stage
> > if the output stage is ever to swing positive. As it is the output
stage
> is
> > going to go full negative until the opamp output blows up. Then it will
> > either stay full negative or swing full positive. At this point you
will
> > have wished you had a (next paragraph).

I found out too that fet op-amps act funny near the supply rails...
set-up as a simple buffer, if the input gets too close to the supply rails,
the output flips over!!! In tests, on +-12volt supplies, with an in of -10
volts or more, the output jumped to +11!! something to think about if
op-amps are used...

Aaron Howald
ahowald@w-link.net
Received on Wed Nov 3 22:55:06 1999