I was always under the impression that he's just alternate picking that single note on the guitar in eighth notes?
Telecaster - SG - Jaguar
Princeton Reverb, Extra Reverb
P-Bass - Mustang Bass
Apogee Duet 2 - Ableton Suite
Yeah, that's just straight picking of the same note, like a drone, with reverb.
Hey, look. Sigs are back.
I don't have a guitar with me right now, but I think they are playing just the E note. To achieve that sound, hold the 5th fret of the h string (b string for some ), but also play the open e string. That way you have the same note on two adjacent strings, and slight difference in tuning will give that "special" sound.
Those are Ramones, there is nothing involved except guitar, cable and a dry marshall The same thing can be heard in songs like Hey Joe by Hendrix (first note in the song) or in Pride and Joy by SRV (intro).