I'm building a sensitive analog circuit powered by a wall wart. I'm using a DCV01 family DC/DC converter with dual outputs (+/- 6.5V) followed by linear regulators. The SYNC pin of the DCV01 converter unintentionally generates a signal that transmits wirelessly...the package's pin acts as antenna I suppose. Bringing a wire near it allows me to see the SYNC pin timing on an oscilloscope. While I have filtered the output of the DCV01 as suggested (I think), some of this periodic ripple (looks like a wavepacket every 1/400MHz) remains. The amplitude is millivolts--way over my noise budget. My circuits operate on microvolts.
I'm attaching an image of the circuit design. It's pretty trivial. How can I get rid of this signal? Is there a standard filtering approach that I should have impelmented?