Note that the 82912/82913 use a BNC input connector.
IIRC
the HP-86 uses a RCA (phono-plug) connector. HP uses a cable
that has a BNC fitting on one end and a phono plug on the
other. Some of the HP 9000 series 200 computers use the same
monitors and cable. Some of the 9000 series 300 computers use
the same monitor but have BNC connnector so they use a cable
with two BNC connectors.
Joe
My HP 82912A has an RCA input - maybe that has something to do with the
"A" suffix?
My 86s work with both the Apple and HP composite monitors. It's the
9920 (aka 9000/220) that uses the 30kHz horizontal sync instead of the
usual 15kHz and requires one of the special HP models, such as the HP
35731A.
-W