On Wed, 13 May 1998, Toru Nishimura wrote:

> It would make you much happier to obtain a decent "multi-sync PC
> monitor"  with BNC connectors behind it.  High end PC monitors take two
> inputs with BNC and HD Dsub15.  You could use them interchangably
> between PCs and DECstations, and save space/electoricity/what-so-ever. 

True, but high-end PC monitors are terribly expensive, and don't most
PC-style monitors with BNC connectors expect their sync signals on
separate lines?

I've been wondering lately about how one would convert a sync-on-green BNC
system to a VGA DB15.  [1] I've been thinking of setting up some kind of
resonant circuit (PLL or otherwise) to sync up to both the H and Vsync
pulses, and then send those directly to the proper pins on the DB15, but
if the impedances on the monitor are high enough, shouldn't it be possible
to take the green BNC connector and hook it to the green and sync
connectors on the VGA DB15?  Will the green input on the monitor be blown
by seeing a +5V sync pulse?  (A quick acting video switch should take care
of that.)  Will the monitor get confused by seeing Hsync pulses on the
Vsync line and vice versa?

It'd be terribly nice to put a head on my DECStations... [2]

[1] Reed College has a bunch of old Tektronix XP25 X terminals, but most
    of them have dead monitors.  They'd actually be somewhat useful if
    they had working monitors.
[2] I also have two Decstation 5000s, both
    with framebuffers, but no monitor for either of them.

----
  Aaron J. Grier  | "Not your ordinary poofy goof." | agrier@poofy.goof.com
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