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HP 9100A No Display - Printable Version

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HP 9100A No Display - aj04062 - 09-09-2017 07:33 PM

Seeking technical help, parts, guidance, you name it to try and resurrect a 9100A model. Previous owner claimed everything worked except the core memory board. This was determined through board swapping with his other machine. I'm now handicapped to diagnose as I don't have this reference.

A few months ago, I checked the power supply to the Service Manual available on HPmuseum.net and everything looked fine as I recall. I've also cleaned the edge contacts and double checked their seating on the main boards but didn't do the sideboards as Tony D calls them.

I do need to check the clock, flip-flops and mains sync signal per Tony's comments on thread

Since this early, simple testing, I commissioned some extension boards to fit into the dual slots. This will allow me to raise the core memory board above the others to probe. Thing is, I don't know what I'm probing for!

RE: HP 9100A No Display - DanM - 09-10-2017 02:13 AM

I am in Southern Vermont and Boston Area, with a 9100B... if this is close enough to you to be useful, let me know.

Dan M.

RE: HP 9100A No Display - aj04062 - 12-16-2017 02:06 AM


Hi Dan,
Sadly the electronics are too different to be of help.

BTW, I will be in San Francisco over the NEW YEARS. If anyone in the bay area has a machine, I could bring some of the boards if they are willing to let me swap mine in to confirm the failed board.