16 Jul
2012
16 Jul
'12
8:43 p.m.
On 16 Jul 2012 at 20:15, Chris Tofu wrote:
and in reality I'm struggling to try and
understand why or what is
torquing the green signal. I've gone the quick and dirty route and
have added sync signals to green w/a resistor. I was rather flippant
in my selection of a value too. Never had a problem. But what do I
know.
Well, I can think of a possible explanation. See, for example, the
waveforms in this Maxim app note about creating SOG from discrete
green and sync inputs:
http://www.maxim-ic.com/app-notes/index.mvp/id/4116
Note that the sync pulse creates a "sub-black" level. If the
monitor is capacitively coupled, this could create a false black
"floor". A sync separator could be used to clamp the SOG green level
during this period to 0V, eliminating the fake green floor.
Just a guess...
--Chuck