CMT- Corvalis Microtechnology


Do you guys remember CMT?

It was a bunch of great HP Engineers who broke off from the HP Corvalis Calc. division to start their own third party
accessories vendor.

I bought the massive 32KB ROM that fits in the card reader slot of my HP71B. Great product, still in full use today!

Anyone know what happened to them?

Are there any good 3rd party HPCalc vendors out there now?

I love this board! Thanks Mr. Hicks.

John Kercheval in VA


I have the 128K and 64K for the card reader slot and 64k, 32K for the front plug-in slots, as well as the 64K EPROM for the front plug in slot, in my 71Bs.

Someday, I'll have to try and build up something to program the EPROMS.


Glad to meet another HP 71B Fanatic. I remember those big roms- out of my price range and more ram than I needed.

Now, I use the 32K Ram plus internal memory.

Tell me more about your 71s. What else do you have? What do you use them for?

Have you tried the 48? Your impessions?

See my post under
" Your best calc."

John Kercheval


Tell me more about your 71s. What else do you have? What do you use them for?

I have several. I have a couple configured with 200K+ of RAM. I have the card reader, Math, Finance, 41 Translator, FORTH, HP-IL, some military ROMs, the usual.

Got my first one the day they first came out. Got it like some of my other stuff by driving down to Corvallis and getting it direct from HP salesman.

I don't actually use them on any daily basis. I have an engineering degree and take one (at least) of my HPs to work most everyday. Just like to give them a little use from time to time.


You could be arrested for that!

The 71B is sacred machine, not to use it is like NOT looking for Mariah Carey's panty lines- it simply isn't done.

200K is a lot- you must have had a lot of online programs.

I assume you are an avid user of the Digital Cassette Drive?

Are you aware of any other CMT products? Didn't they made a HEATED case for the 71b?

John Kercheval


>Didn't they made a HEATED case for the 71b?

Do you mean that the CMT organization made a large contribution to the advancement of the HP71B platform, or are you saying they actually manufactured a calculator warmer? Was that to allow the LCD to work in low temperature environments?


I believe someone made an electrically heated case for the 71B for harsh environments. Unsure if it was CMT. It was sold via EduCalc. Where is Jim Carter when you need him?

John Kercheval



I think it was the 'battle-case'.
Maybe Tripod Data Systems (TDS) made something like this.
At least they made the battle case for the HP-48 and their surveying pac, with optional built-in extra RAM.




Yes! I stand corrected, it was TDS.



200K does not mean I need that much. I have it because it is something to have. Who has to justify it?

If you had to justify having it, I'd never be able to justify a house full of calculators.


A quick search (i.e. yahoo) on "corvallis microtechnology" will result in

These guys make GPS (global positioning system) stuff (now). I don't know if they are the same folks referred to here, or a descendent, or just so good a name it had to be resurrected.



cmt also made a calculator/handheld computer. it may have been called the cmt 500; i'm going on faulty memory here. it had a screen and keyboard similar it size to the 48 and was about twice as thick. it used a low power version of some ibm clone chip and had a (for the time) massive memory. i played with one that had a surveying program for a couple of hours and it was really impressive for it's time - which was pre hp 48sx. it's only problem was that the (well made) case was designed with vent holes and you could see the mother board. that would be ok in an office but in the real world i think it would have to be covered or the dust would kill it.


Yes, I remember that device well- it was an IBM machine with a 286 platform. I only saw it in ads, never in real life.

John Kercheval

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