Automatic video switchers

[kendrick]

Long story short, I've been hunting down one of these:

http://www.naki-world.com/55728.html

They're out of stock everywhere, and the usual online places claim to have them but don't really. My plan was to daisy-chain a few of them together so as to avoid having to press buttons when switching consoles. I noticed that Naki has a couple of versions, some with four inputs and some with six. I can't imagine that the circuitry differs too much among the models. Either it's a modular circuit that's easily repeated for each input, or it's an IC with a number of inputs that go unused.

Anybody have any ideas about what might be in this thing? Most of the components for automatic video switching seem to be focused on CCTV applications, but if this is an off-the-shelf item too then there's no reason why I couldn't build my own. For a change. :)

-KKC, who should really join the 20th century and start using component video...

[viletim!]

I dunno exactly what inside....but it'd have to be cheap considering the low RRP.

You could build one relatively easily using some ICS: a couple of analog switches (4053) - one for each signal - ie. 3 for video + left + right, a video detector (LM1881), a counter (4020, 4024 ,something like that), a slow clock source ~2Hz (555 timer) and a video buffer (discrete components or a fast op-amp).

I can give you more info if you like but it would probably be cheaper/easier to buy another model auto-switchbox that is available.

[kendrick]

Thanks Tim, but don't go to any extra trouble. I'm guessing that those Naki boxes have all the components you're describing in a single, consolidated chip. Ideally, we get ourselves a few dozen of those and createa a giant, rack-mountable box that accepts dozens of connections and connectino types. I've found a reasonably-priced source, so what I'll likely do is buy a couple and rip 'em apart to see.

-KKC