Screen Brightness Control Disabled

[sjameson@hannibal.atl.ge.com (Stephen M Jameson)]

We have several Symbolics, three of which have the old-style (3600) monitors,
and the rest of which have the newer (XL) style monitors, although two of the
latter are actually 3650's.  Something has happened recently which has caused
us to lose brightness control for all of the newer monitors.  None of the
conventional mechanisms are working: Local-D, Waiting 20 minutes, SETF-ing
(TV:SCREEN-BRIGHTNESS), plus one or two other things I tried.  I don't know if
it is a hardware problem or a software problem (which I suspect, since it
happened to all of the machines at once).  I tried re-booting and even shutting
down and restarting one of the machines, and it still does not respond.  All of
the other LOCAL-* functions work:  LOCAL-G, L, Q, C.

Has anybody encountered this before, and does anybody have any solutions?

Steve Jameson                           General Electric Aerospace 
sjameson@atl.ge.com                     Advanced Technology Laboratories
                                        Moorestown, New Jersey              
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**  for its swiftness, nor the warrior for his glory.  I love only that   **
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**    -- Faramir, "The Two Towers"                                        **
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