It seems to be a circuit to generate PAL-N signal. PAL-N (mainly used in Argentina) has an NTSC-like subcarrier frequency. Used on a normal PAL tv or monitor, there will be no color at all. Changing the subcarrier frequency will effectively solve the problem.Borber said:This TV Pattern Generator has failures in sync timing. It does not comply to PAL standard (jitter on fields). But on most TV receivers it does not make problems.