The lid appears to be flipped over, as if on a hinge.
A conduit is a tubular structure used to carry wires, not the wires themselves.
It is common in electrical installations to have different colored hot wires, with white being neutral according to standard. Black is usually hot for circuit 1, red for circuit 2.
It s not uncommon to have more than one hot wire per neutral.
What you seem to be calling yellow appears brown to this anon. Either way, both are common color codes to help identify circuits. Look at wire on homedepot.com or something.
The round, what you call object, in the bottom appears to be a hole in the base looking into the dirt to this anon. If it were an inductive coil, it would use smaller wire with more turns to increase sensitivity and, in any case, would need to be overran directly above the box in the given orientation.
In ANY case, I see no electronics to condition/process/relay ANY signals so, what's your point?