19 Jul
1999
19 Jul
'99
10:15 p.m.
On 19 Jul 99 at 21:02, Richard Erlacher wrote:
The GDM1950 that I had for a couple of years required negative-going sync.
The PC may not be generating negative-going sync, but you can bet it will
generate negative-going composite blanking! What's more, the GDM1950 I had
was complete with a switch which enable sync-on-green decoding, and it's
likely this one has it too. That provides an alternative to figuring out
how to switch the polarity of the sync the card puts out. I've never been
particularly good at that sort of thing, hence once built a little adapter
with XOR buffers, each of which could serve either as a buffer or as an
inverter, depending on how its "other" input was jumpered.
I have a couple of old multisync monitors that have this switch, as well as a
dig-analogue switch but this GDM 1950 doesn't. It would have been helpful if
the different versions of the "1950 GDM" had some consistencies or else a
sub-model #. Makes any specs you get suspect.
ciao larry
lwalker(a)interlog.com
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