Zephyrs:
Hey. Two main questions.If I increase the PWM frequency, noise on nearby wires should reduce? I'm running a twisted pair carrying composite video next to my power cable running PWM, and at around 40% duty cycle, the picture gets so corrupted that it's unviewable. Would increasing PWM frequency help?
I guess you are assuming that there is a "coupling" of sorts between the pair carrying the PWM signal, and the pair carrying the video...what Category cable are you using?
If you are using good quality CAT-5 or even CAT-6, I think this should not be the case....but if it is, then I think you should use the twisted cable to carry say the digital signal, and maybe break out your video signal to a good quality shielded cable....
this might resolve your issue... varying the frequency will have an effect on the coupling, but if you really have this much interference, I do not think it will help much...