tcpl123 wrote: The reason I went for the remote option as opposed to attempting to shield the transformer is that the mod is completely reverse-able if I sell the board and there was always the risk of putting in all the effort and being unsuccessful (EME can be tough to contain). Also the space is limited inside and there could have been over heating issues.
I totally agree with your approach. I expect at the low frequency of the transformer the coupling is primarily in the magnetic field. Magnetic fields are usually hard to shield without exotic materials, so the simplest solution is increasing the distance between your guitar pickups and the power supply.
Thanks for looking into this. Earlier entries in the forum suggested that internal shielding of the transformer might suffice. I hope you can provide some empirical evidence to support or contradict that theory.
-pterm