HP-71B Memory Modules


Based on postings in the archive, there were 4k, 8k, 16k, 32k and 64k RAM memory modules that were once available for the 71. One maker of the 32k and 64k (Card Reader Bay) modules was Corvallis Microtech.

My question is: What was the largest RAM module that HP ever made? Was it the 16k module?


Corvallis also made a 128K memory module for the card reader bay.


Talking about MMs for the 71B, I've a 32 as well as 64 KB MM installed in my machine. The 32 Module can be removed from the machine with some effort and care but no way for the 64 Module. It sticks that tight in the slot that I fear to break it when trying to get it out. I guess, this is due to the fact that the machine used to work in a hot environment. Any suggestions/procedures on how to manage to get it out without damage?



at least for tight fitting HP-IL modules,
I (carefully) insert a thin screwdriver from the opposite side of the case, and push the module out.
I your 64K module sits in port 1 or 2, this should work the other way round.

I also made the experience that my CMT 32K modules won't get out w/o some force.

Maybe they thought 'Safety first';-)




Thanks for the advice, Raymond. Actually, I do have a tight fitting HP-IL too and do use a similar procedure you described to push it out. I didn't consider to apply this to the MMs in port 1,2 as I always felt the housing of the MMs being much more fragile (or brittle) than that of the HP-IL. However, I agree that the procedure could be succesfully applied to MMs as well if carried out with (great) care :-)


There is the philosophy: "If it jams, force it. It if breaks, it needed fixing anyway." As long as it works, I'd leave it alone.

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