Red Baron display problems: likely suspects?

Hi,
I'm trying to fix a Red Baron that only displays the bottom half of the
screen (monitor is OK; no mathbox errors; in fact, no errors at all in test
mode). On the main board, I replaced the transistors at Q3 and Q2. I've
pulled and soldered in sockets for the LF13201 at D11, the LM319s at B12 and
D12, and the TL084 at C11. I'm going to order ICs to replace all these;
anything else I should order while I'm at it?
As always, thanks for any comments, advice, snide remarks!
Lewis

----- Original Message -----
From: "Lewis Mills" <lmills01@home.com>
To: <vectorlist@synthcom.com>
Sent: Tuesday, September 18, 2001 9:19 PM
Subject: Re: VECTOR: The plane! The plane!

> Hi,
> Well, I don't think there are mathbox errors. Since the display is only in
> the bottom half of the screen, maybe there is a mathbox error and I can't
> see it. I don't see any text on the test screen, not even the switch
setting
> readouts.
>
> I pulled, not just the PROMs, but every socketed chip on both boards and
> lightly cleaned the pins with a pencil eraser and reseated them.
>
> Also re-soldered all the connector pins and checked continuity on all the
> wires on the main-aux connector.
>
> I'm tantalizingly close, and not sure what to do next....
> Lewis
>
> > -----Original Message-----
> > From: owner-vectorlist@synthcom.com
> > [mailto:owner-vectorlist@synthcom.com]On Behalf Of MKDUD@aol.com
> > Sent: Tuesday, September 18, 2001 12:29 AM
> > To: vectorlist@synthcom.com
> > Subject: Re: VECTOR: The plane! The plane!
> >
> >
> > In a message dated 9/17/2001 10:53:33 PM Eastern Daylight Time,
> > lmills01@home.com writes:
> >
> > << So, I'm thinking the problem is in the Red Baron aux board. Somewhere
> > along
> > the line that makes up the X signal. Has anyone seen this problem? >>
> >
> > Are you getting any mathbox errors? Have you checked all the prom
sockets,
> > as
> > well as the interconnect between the AVG and AUX board?
>
> --------------------------------------------------------------------------
> -
> > ** 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 Sep 24 17:41:53 2001