Hello List and Conrad H you said: I've not seen this arrangement before, but I'm trying to figure out the string terminus. Does what looks like a brass valve cap (to continue bicycle analogy) spin off to reveal some sort of attachment point?" Yes. But if I remember right you have to prise it of (carefully) and the end of the string is bent over and captivated by that cap. I thought I was the only living person to have seen this device - that was about 30 years ago in Sussex University. Have phun Regards from windy Sussex-on-Sea Michael G (UK) TGIF
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