I found that AD725 requires TTL levels for 4FSC but I could not find NTSC crystal which is 5v! so I thought will a 3.3v crystal work fine??
as seen in my picture, the circuit is simple. I have a SP3T switch (or any mechanism) that feeds 0v for choosing PAL, 3,3v for NTSC or just another throw for auto detection (circuit not shown here). this circuit needs more tuning but you get the idea.
I really need very easy and stable solution which doesn't require tuning...
so can AD725 accept 3.3v crystal signals?
what crystals do you suggest? I need some part numbers please since finding them is very hard now.