[oldeurope]

Gidday,
I need some suggestions how to switch the colour trap at the input.
The colour trap is switched on when Q7 is switched off and vise versa.
So if there is a current flow from base of Q7 via a 22K Ohms to ground, the
filter (trap) is switched off.
If R41/33/40 and D5 are not loaded, the trap is switched on when the converter is standard converting. With a 10KHz (405) signal at the input it
switches automaticly to bypass. The collector of Q5 goes to ground thus
a current flowes from base of Q7 via R37 to ground.
So in the bypass mode the filter is switched off.
Disadvantage, the filter is always switched on when standard converting.
But if your source is monochrom (Y out DVD) you don't want a trap.

Now I added JP4. If R37 is not loaded, the filter is only switched on if a
cvbs signal is applied via scart. I made this solution in the MK II and III.
For me this is ok. What do you think?
Any better ideas?

Kind regards
Darius