I'm using the AD725 as RGB to NTSC converter (composite video output).
I use an RGB input signal from a RGB generator that has several distanced vertical lines.
The Composite output has a shadow on every vertical line because of the YTRAP filter.
I use the recommended values for C, L from the datasheet and I get this shadow (because of the filter)
When I increase the Q factor of the filter (narrow filter) I get color artifacts on the output signal (The YTRAP filter is hardly helping to remove the chrominance) .
When I decrease the Q factor of the filter (wide filter) I get more shadow.
You can see the attached filters that I used 3 type of filters. the input is the green signal on the bottom (variable frequency over one line). the output is the composite signal that if filtered.
Every file name has a the values of L, C.
I also used an RGB generator that inputs a text to the converter and got shadowed text.
I can not use the YC output. I must use composite output.
How can I improve the sharpness of the output signal without having colors artifacts on the output?
Is it a limit of the converter or is it a correct response to a vertical single line?