I’ve been repairing a few broken old pickups recently so thought I’d share some pictures and thoughts on this classic old Gibson T-Top.
The T-Top is a fairly common pickup on my workbench. Not because there’s and common fault with them but simply there were so many made and they’re all getting quite old now.
The “T-Top” simply refers to the molding on the top of the bobbin. They were Gibson’s standard humbucker from 67/8 until around 1980 replacing the legendary PAF.
There were a few subtle changes from the PAF but enough to make a difference.
Although the bobbins look different the important dimensions were unchanged and they are still made of butyrate making it impractical to wax pot them. Butyrate distorts with heat.
The wire is poly insulated instead of the plain enamel used on PAF’s. Pretty much all T-Tops have a dc resistance of around 7.5 KOhms, neck and bridge the same. The coils are wound symmetrically and are unpotted so beware of squealing with high gain.
The magnets varied, often Alnico III, V or even Ceramic.
This one came to me with a dead coil in need of a re-wind. the magnet is a rough cast Alnico V and from the good coil the finished dc reading I was after was 7.4 KOhms.
After the re-wind I gave it some new cloth tape so it looked the part and it was ready to ROCK.