Re: Monitor video output

[Doug Evans <DE@phoenix.sch.symbolics.com>]

    Date: Fri 11 Nov 88 00:47:51-PST
    From: TYSON@Warbucks.AI.SRI.COM (Mabry Tyson)

    It is also rumored that you can pull the video signal out of the
    monitor somewhere.  (Remember all the warnings about opening up
    anything that is under warranty (and maybe even maintenance) and only
    trained electronic technicians should work on it, etc.)  We have not
    attempted to get the signal out of the monitor here.

This really is a better idea ... after all, there is already a decoder
in the console.  The problem is to get the three decoded signals (HSync,
VSync, and Video) out of the box without doing major kludges.  One
possible alternative is to hack the controller board such that unused
lines at the DIN audio connector carry the signals.  This 5 pin
connector has one channel of audio and ground.  I don't presently have
the console controller schematics here at my desk (as Field Service
doesn't troubleshoot to the component level), but I'll look into what
specifics are necessary for such a mod.  As this is such a simple thing
to do (maybe as simple as three wires added to the controller board), it
may even be possible to do it in such a way as to make it "legal" for
warranty and contracts.

    I believe that at one point we priced the decoder unit mentioned in
    the message and found it to be much too expensive for us.  If someone
    knows of a decoder under $1K, we might be interested (so please let me
    know).

Good luck ... It costs us $750 in parts alone to build the decoder
ourselves.  Remember that we're talking about 80MHz ECL digital and
video components here ... not a pile of off the shelf TV parts.  There
is a price to pay for the high resolution and information content of our
screens.

    (Tech. support:  Thanks for posting the info...)
    -------

Although technically its not part of my job, I monitor SLUG and try to
help out with hardware problems when possible.  All questions welcomed.