Thanks for the info. I can remember using it with the grounding sleeve when the kit was complete and there were various adpators with it. Sadly, these are long gone. I may try searching for them at work in some of the RF adaptor storage boxes.
There is some good news though... I removed the original power feed and wired up to external supplies and it all seems to work fine
I've included the series 120R resistor for the -15V rail and this now lives inside the probe body.
I'm quite pleased with my first bodged attempt at an RF ground sleeve and spike. The metal I've used is a special springy alloy and it fits and grips very snugly. I have to twist and pull it quite firmly to get it off as the probe outer is ribbed under the sleeve area. I recall that the original sleeve spike had a ferrite bead near its tip. Do yours have this?
I've tested the probe for response up to 1GHz at various attenuator settings and it seems fine. See below for my fudged connections. Ultimately, I'd like to refit the power lead as per original and I'll do the same as you in that I'll find a way to connect to some clean supplies via the original power connector. The crude wire mods I've done are all reversible so I can get it back to original very quickly.
I'll obviously have to insulate my homebrew earth sleeve on the outside. But for now I'll just wrap some insulating tape around it
I'll do some linearity and input impedance tests on it at some point in the next few days to prove it really is all OK.