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Abekas A53D Question



Maybe a little advice is what I can offer. 

There are plenty decent new and used  A/D & D/A's available, almost any
manufacturer with selfrespect makes a them. Just make SURE that they have CCIR
specification filters, use 10bits quantisation on both coding and decoding and
that they handle auto switching of 50/60 frame rates. Also check that the device
does not behave oddly with the analog levels in the various formats. A built in
bar/pattern generator can be very useful in setting/checking the system. Also
the more alternatives you have for syncing the box the better (sync on green, on
Y or separate comp sync and BB). 

Obviously the A/D must gave RGB+S input and do a good job of transcoding to YUV
which is the format you shall feed the rest of the system with (I'll get flamed
for this but commeth prepared, ha!)

Note that correctly designed D/A and A/D have matched filters not only within
each device but even in some cases between the two boxes, so preferably do not
mix brands. 

There is one physical check to do before you part with your money, mechanically
check (shake) the box with signal going through. It is not uncommon with bad
contacts on the CCIR filters.

Bon chance.

Mike Reichel