extracting H/V sync from sync-on-green video signal?

[Eric Smith]

Jules Richardson wrote (regarding sync separation):
> Unfortunately I don't have an LM1881 chip in the spares pile :-(
> I could have sworn there was an easier way though

Jochen wrote:
> You can use an OPA wired as a comparator too. Set the switch level to
> about 0.15 V and you get C-sync out of the comparator. The black level
> of a video signal is 0.3 V. Everything below down to 0 V is sync. You
> should use a TTl IC behind the comparator as a line driver.

Won't work reliably if the video is AC-coupled, which is *very* common.
The LM1881 (and the improved-spec EL4581) are designed to deal with
that.