Re: Cinematronics monitor help

I believe I still have a couple of the LF13331's in stock. I'd let one go
in an emergency. Sell or trade..

John :-#)#

At 10:05 AM 25/02/2002 -0800, Matt Rossiter wrote:
>I think the breakers will trip if the LF13331 analog switch is bad. I
>fixed an
>early space wars monitor that had that problem.
>
>You might want to try swapping the analog switch from the a working
>monitor. Be
>
>really carefull though - they are hard to find.
>
>You should also look at these service notes if you have an older monitor.
>
>http://www.spies.com/arcade/schematics/cine/serv3.tiff
>http://www.spies.com/arcade/schematics/cine/serv18.tiff
>
>Matt
>
>Mark Jenison wrote:
>
> > > It sounds like you are only getting chatter in one channel, and that the
> > other
> > > channel is pegging the yoke to one side, causing the circuit breaker to
> > blow.
> >
> > Is it possible to run the monitor with just ONE yoke winding connected
> (just
> > x or just y)? That way I could narrow down which circuit is failing.
> >
> > > Check the power transistors, using the standard diode setting on a VOM,
> > and see
> > > if any are shorted.
> >
> > Hmm...I replaced the transistors and they still test fine, unless one is
> > failing under load. Maybe one of the DACs are bad...
> >
> > > >BTW, the Cine monitor doc on spies says to unplug the harnesses to the
> > heat
> > > >sinks and leave the yoke plugged in to get "a smaller picture". I tried
> > > >this once before I got this far and it burned up a bunch of resistors.
> > >
> > > That is a really bad thing to do. Unplugging the heatsinks causes the
> full
> > load
> > > of the yoke to be handled by a couple of small pre-driver transistors
> > through a
> > > couple of 47ohm resistors (which is probably what you smoked before). Who
> > ever
> > > recommended this must have inhaled too much of that resistor smoke.
> > >
> > > Now if there were some test software that generated a very small picture
> > in the
> > > middle of the screen, small enough as to not overload the small
> pre-driver
> > > transistors and resistors, this could possibly be a valid test.
> > >
> > > I'd have to look into the pre-driver current loads, to verify that a box
> > small
> > > enough to keep from overloading the pre-drivers, and yet large enough to
> > be
> > > useful, could be drawn.
> > >
> > > If anybody is interested in such a program, I'm sure I could have it
> > written by
> > > the end of the week. (Given my current schedule.)
> >
> > I'm for anything that helps debug these monitors.
> >
> > --
> > Mark Jenison
> >
> > ---------------------------------------------------------------------------
> > ** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
> > ** message body to vectorlist-request@synthcom.com. Please direct other
> > ** questions, comments, or problems to neil@synthcom.com.
>
>---------------------------------------------------------------------------
>** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
>** message body to vectorlist-request@synthcom.com. Please direct other
>** questions, comments, or problems to neil@synthcom.com.

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Mon Feb 25 11:24:36 2002