[sdiy] [AH] analog video synthesizers

[Grant Richter]

> 
>> Any leads on an NTSC Video Interface Module?
> 
> I am trying to design one now. Stick around.
> 

Without bragging, I did this 20 years ago. I still don't think there is
enough of a market for a commercial product. The Wiard modules are all
roughed in for video work. With a cap change the Classic VCO will run up
into the megahertz range, with synchronization.

I checked on parts availability for a minimum parts count Sandin Image
processor.

If you go to Mouser and search for CD22402, it will provide the NTE cross
for $18 or so. This is the full sync generator. You can gen lock it to the
LM1881 using a CD4046 to provide the high frequency clock.

The LM1881 sync stripper is still in full production according to the
National web site.

The Motorola MC1372 RGB to NTSC encoder can be had from BGMicro for $.50
each.

The 300ns delay lines for time aligning the luminance signal can be still
gotten from Digikey, TOKO makes them, but they are $10 each.

The original image processor design is at

http://artscilab.org/archive/Artists6/Sandin/Feb28,1976.pdf

that should provide the theoretical background.

A video "color corrector" will contain all the circuits needed for video
synthesis. i.e. sync strip & regen, NTSC to RGB and RGB to NTSC. The easiest
method is is probably to get a $120 color corrector like this one

http://www.bgsales.com/electronics/scc.asp

and patch it out with buffer amps. You should use CD4066s or the like to
enforce the blanking period on inputs to the RGB to NTSC encoder.