Chinese Forehead made use of assorted low-tech gear for a variety of effects. In addition to the use of a vibrator, a hacked open-reel tape recorder was used to run tape loops.
The device was pulled from some street-side trash one day. You can kinda-sorta see a picture of it in one of the posters for the Nov 15 1979 TR3 gig.
It looked somewhat similar to this image:
It was big, clunky, and fun to hack.
Such devices work by altering magnetic tape as it passes over the tape head assembly. On this device the record head preceded the play-back head. If you sent an audio signal directly to the record head the sound would be recorded on the tape and immediately played by the playback head.
One result was a cheap, short, delay.
If you did not send any audio signal whatever was on the tape would play. By using lops of various sizes in place of the standard reels a section of sound could be repeated endlessly.
To provide a signal, an electric guitar (a 1976 Fender Stratocaster) was run through a Pignose Amp. However, instead of outputting to the speaker, the speaker wires were re-routed to run to the record head for the tape loop.
The loop was used for some performances of the B Song and Altitude.
Live use was discontinued because the set-up was prone to failure at just the wrong moment.