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HP Forum Archive 20

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HP-67 Error message
Message #1 Posted by aj04062 on 14 May 2011, 2:27 p.m.

Hi ya all,

Seeing there is some activity regarding 67's, who can tell me what is ailing this unit? Is the processor fried? I picked this up from Goverment Auction (los alomos lab source)

Note: I have the back off and am pressing down to make contact. It is behaving the same way before I took it apart.

Please see the video below.


Pressing keys will halt the cylcling. It will everntually stop and seems to repeat the same code.

Re: HP-67 Error message
Message #2 Posted by BobVA on 15 May 2011, 8:51 a.m.,
in response to message #1 by aj04062

"Could be a lot of things..." How's that for helpful? :-)

First, don't try reading any more cards until you take a look at the friction roller for the reader - it's probably turned to goo unless somebody has replaced it. (Although I'm somewhat surprised it actually pulled the card through on yours...)

The problem could be as simple as a bad battery - have you checked the voltage? Tried running it from a bench supply?

The next lucky break would be a bad/dirty connection between one of the three internal boards, a dirty power or run switch, etc. That will require disassembly. If you want to try that, check out the guides here. Disassembly requires some experience working on electronics and small mechanical gizmos. The guides provide enough information/photos to let you decide if you're comfortable with trying it.

If you don't want to try a repair, I'm sure you can sell it easily here or on the 'bay as a parts unit.

Regards, Bob

Edited: 15 May 2011, 8:57 a.m.

Re: HP-67 Error message HP-65 common parts?
Message #3 Posted by aj04062 on 15 May 2011, 9:25 a.m.,
in response to message #2 by BobVA

This wheel actually looks very good. I am amazed.

I've tried a new battery (worked on other 67 I have). I don't have a bench supply so that experiment is out. I will check voltage and make sure it is fully charged.

I'll try some deoxit on the contacts. I cleaned the switches with iso-alch already.

does anyone know what boards are interchangeable between the 67 & 65? I have a 65 with a card reader board that has been ravaged by a leaky battery. Can these be swapped?

Re: HP-67 Error message HP-65 common parts?
Message #4 Posted by Randy on 15 May 2011, 1:32 p.m.,
in response to message #3 by aj04062

HP-65 Internals

HP67 Internals

The only thing the two boards have in common is the same 28 pin connection area :-(

Hard to tell what is wrong but based on the most common 67/97 failures, I'd suspect a faulty rom.

Edited: 15 May 2011, 1:34 p.m.

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