The Airline Pocket Bass has a pickup inside the the bridge….who knew!? It has magnets that hang down from the adjustable saddle through 2 coils embedded in the wood base. On this example I found that one of the coils was not functioning and had to rewind it.
In this case I found that 12000 winds of AWG 44 wire yielded a resistance to match the other coil, 3.4k ohms.