G&L tech resources: Pickups

 
 

The guitar version of the Magnetic Field Design (MFD) humbucker was also introduced in 1980 on the F-100 model. Initially, cheese head slotted machine screws were used to adjust the height of the pole pieces and, similar to the early bass MFD humbuckers, no “PAT 4220069 is printed on the cover. But by the end of 1981, the pole pieces have changed to socket (Allen) head cap screws and the cover now includes the patent number, as seen on this mid-1982 F-100 Series II. The spare early F-100 pickup pictured below shows 4 leads: a yellow lead soldered to the copper baseplate, a white lead soldered to the start of one coil with a DC-R of 3.73kΩ, a green lead soldered to the end of the other with a DC-R of 3.76kΩ, and the black lead effectively connecting the 2 coils. The DC-R value between white and green leads hence is 7.49kΩ. Note the presence of a 2.2kΩ resistor near the green lead. It seems to go to ground and its function is not clear. Also note that each coil has its own bar magnet underneath separated by the plastic wall of the cover. The humbucker on the G-200, a model offered between 1981-1982, differs in 2 aspects with more windings on the bobbins combined with a weaker magnet, an approach also seen when comparing the S-500 vs. Nighthawk MFD single-coil pickups. With its different scale and tone stack, the G-200 has its own and, as claimed by many, better sound. It seems the G-200 pickup cover has always been void of the patent number. The F-100 disappeared from the price list in 1983 and with that effectively this humbucker even though F-100s would be built on occasion all the way up to the end of 1991. Fortunately, this MFD humbucker was resurrected for the 25th Anniversary model in 2005 and used on the (reintroduced) F-100 between 2007 and 2017 and is hence referred to as F-100 MFD on G&L website and in its store. These later pickups of course include the patent number on their cover.

 

Guitar: MFD humbucker