8. Single Coils
Single coil wiring is generally fairly straightforward. The classic design has two connecting leads - signal and ground. The signal leads are connected to a selector switch. The original Stratocaster design had three positions the switch had to be carefully placed between positions to connect two pickups at once. This practice quickly became so popular that five-way switches are now standard.
The Hum Problem
Humbuckers are popular both because they meet their original design goal the elimination of hum and because of their distinctive sound. Many guitarists prefer the single coil sound, however, so pickup designers have found other ways of addressing the hum issue.
The Lace Sensor is the most successful and influential of these designs to date. Radiant field barriers block outside interference, and the design has other advantages including improved sustain. Lace pickups were originally exclusively licensed to Fender, notably on the Eric Clapton Signature Stratocaster.
DiMarzios approach is slightly different a best of both stacked humbucker design where the bottom dummy coil picks up noise only. This cancels noise from the top coil and the two are separated by a magnetic shield to reduce interaction, so the single coil sound is faithfully preserved.