christophervalle saidPutting boxes around components or sets of components in the DS Jr could indeed mess with needed air flow and might risk a future short circuit in either the Jr or Sr. Little square tabs of EMI dampening (not shielding) on top of the aforementioned bigger chips (NOT the power supply regulators in the DS Jr.) is worth trying for the adventurous (they don't run hot), make sure you can remove it if it doesn't do what you want.If you go nuts trying to shield different components inside the case, are you not at risk of either a) redirecting RF from one place to another, and/or b) messing up airflow for cooling?
EldRick saidOnly the power supply caps on the power supply card. The DS's analog card doesn't have any electrolytic caps near the analog section - it uses film for the audio proper and high quality low impedance 8 legged caps for power supply bypassing, local power storage. In the DS Sr it probably wouldn't hurt things to try to dampen the electrolytics that are there, but in the Jr they need all the heat radiation they can get.You might consider adding resonance-damping to the caps. I’ve seen this done as part of many aftermarket electronics upgrades. Theory is that the caps have some mechanical resonance, and that this can quiet the unit noticeably. The usual technique seems to be putting a circular piece of self-stick damping material on the flat end of the caps.
emailists saidTurning the display off will quiet some audio noise down about 120dBFS - it's audible for some. Even so the display processor/control processor is still a big RF radiator which might have more of an effect in some systems than others.Does having the display set to turn off (which is how I usually keep it set) negate the need to treat the board for rf?