|
Mosfets are one component that would actually add value, being Cu. Particular mosfets actually act like ICs sometimes with dies inside them but not considered an IC itself. Most Radio and sound equipment carry those kinds.
Components needing removal for upgrade would be like, electrolytic capacitors, transformers, ferrous materials, plastics and adhesives, larger bonding wires or simple voltage diodes/runners, ferrite blockers, basic resisters, epoxy caps, etcetera, etc.
Depending on what metal box you're talking about, it could be an oscillator or a vapor capture box. Vapor sensors are usually in metal boxes and/or round circular shapes close looking like batteries or a small speaker.
Most push button gold points are just flashings or foils but some can be thicker or actually have a bread layer of gold, inside , the PCB. It's pretty prevalent when you see the difference between the two. The PCB will have a heavy coating in and every hole or touch point.
Like always the best chances to identify or pick out questions is ask the forum for opinions. Remember to post those pictures so we can have an idea of the other one you mentioned.
|