Re: New Vector Monitor Project: LM3886

Rodger, you're not raining on a parade at all, and don't stop criticizing
designs, otherwise I won't get something that works.

The specs on the LM3886 looked ok to me, but maybe it's time for me to do
some actual current and voltage waveform measurements on Tempest to see if
it's too demanding for the use of such a device or not. I don't think that
we are running over 50 watts of power through the yoke.

I'll let you know what I come up with on those measurements!

Thanks,
James

----- Original Message -----
From: Rodger Boots <rlboots@cedar-rapids.net>
To: <vectorlist@lists.cc.utexas.edu>
Sent: Friday, November 05, 1999 1:53 AM
Subject: Re: New Vector Monitor Project: Microprocessor, etc...

> James Nelson wrote:
>
> > I'm looking carefully at the National LM3886 Power OP AMP for direct
yoke
> > drive, and it doesn't cost the $100+ each like some of the other <choke>
> > cool ones do, and it has all kinds of protection circuitry, and Class AB
> > circuitry.
> >
> > Rodger is going to look at the LM3886 to see what complaints he might
have
> > with the device, and I might throw up a proposed 1st order schematic for
> > that circuit soon.
>
> Well, I've looked at it and have some serious questions if it has the raw
balls
> needed for a color vector monitor. B&W, maybe, but I think it's going to
keep
> shutting down running color, even with massive cooling. Especially on
games
> that overscan the monitor.
>
> Yeah, shutting down will protect the IC, but how many times can you
collapse the
> sweep on a game before you burn a big cross in the middle of the CRT.
We're not
> talking losing one half of a screen here, we're talking collapsing into a
line.
> Or worse yet, a dot if both channels dump at the same time. The spot
killer had
> better be damn fast.
>
> I hate to keep raining on this parade so would someone please tell me I'm
full
> of it (and be ready and able to prove it!) already?
>
>
Received on Fri Nov 5 07:13:22 1999