I'm trying to use my Apple ][ as a text generator for my Panasonic MJ-MX12 mixer.
The device allows for an external camera for chroma key duties, it requires that the camera signal be in sync and and external sync for the camera is provided.
The Apple ][ is a very cost effective beast so I realise Woz may have designed it in such a way that I cannot just get the raw luma signal without sync. (I'm hoping!)
I don't need colour, I just need the monochrome signal (which is all the Apple really provides, right?) that I can hopefully merge with my "External sync" (which I assume is a black-screen NTSC signal)
I have an Apple ]]+, //e //e enh., //c units.
I'll take whatever I can get to get a functional system.
If it's not possible to get the signal I want, is it possible to remove video sync to reinsert a new sync? I've seen sync separator ICs...
Sadly the Apple II plays fast and loose with the NTSC standard so it is usually not a great choice for this kind of application. I've seen people kludge together solutions that worked for them though, such as using an old VCR to clean up the Apple II's signal. If I remember right people liked the Sony Beta decks for that. Not that one of those is going to be very easy anymore. But possibly free or nearly so if you find one because I can't imagine anyone wanting one. Then again maybe it is a collector's item these days and all the ones I saw dumpstered back in the day would be gold now... Alas.
The issue is not Apple's less than perfect NTSC signal. In this case, you will never get it to sync with your other video sources which is necessary to combine 2 video signals. Apple actually made the Video Overlay Card for this exct purpose. And it just so happens that Sean Fahey has a couple of those available right now on FB.
Well, there's the answer then... I imagine the video overlay card also has to standardize the signal, because a lot of studio geat back in the day wouldn't even accept an Apple II's signal or if it did it often had weird colors or interference patterns in it.
Some IIe motherboards have a mono/colour switch. I know the PAL IIe ones do. A colour killer was also added to later Apple II variants. This would have been a popular feature considering that monochrome monitors would have been used more often than colour monitors at that point in time.
TTL /Sync signals are available from the IIc's video port or the IIe's 60 pin auxiliary connector or from certian chip pin legs if you are going to use the Apple II (look at the manual for a2heaven's "Apple II VGA Scaler" card for pin details). Your mixer may not accept a TTL voltage signal level so in that case you will need to lover the voltage of this signal to Composite Sync levels.
Good luck.
The issue is not one of removing or adding back in new sync. Unless your video mixer or switcher has a frame synchronizer built in, you cannot mix two un-synchronized video sources. Period.