|Re: A viable vintage data aquisition system?|
Message #2 Posted by Garth Wilson on 5 Mar 2010, 2:24 p.m.,
in response to message #1 by Timo
My first automated test equipment (ATE) system contact with a 41 used the HP3421A data-acquisition unit with HPIL. It was like a DMM with relay cards also to do some controlling, not just taking data. The company got a loaner 3421A from HP to evaluate for buying. Most of the engineers in the engineering lab had their own HP-41's, and my friend used his on this and took 20 minutes of his lunch time to write the program and get it going.
It was an instant hit, being so much less expensive and easier to program than the other millions of dollars of IEEE-488 equipment and controllers the company had. A requisition was put in for a set, but management wounldn't approve the 41, saying it was too easy for someone to put it in their pocket and walk off with it. Instead, they got an IBM PC with an IEEE-488 card, and three weeks after it came in, the two engineers responsible for setting it up were still trying to get the PC and IEEE-488 card to be friends.
A couple of years later, I was at another, much smaller company that was starting to need some ATE. I had my own 41cx by then (1986) and started using it with the HPIL-to-HPIB (IEEE-488) interface converter (HP82169A) to connect to equipment on the workbench to automate the repetitive jobs of taking certain readings through the DMM, and controlling signal generators, relay boxes, power supplies, and so on. In small but quick steps, the company got into a product line that required a lot of testing that was totally impractical to do by hand. Not realizing how quickly this situation was going to escalate, I set up automated testing, using my HP-41 as the controller. Especially back then in the late 80's, people would be absolutely stunned to see a large rack of instrumentation controlled by something that would fit in a pocket. It gradually got to where I didn't get to use my HP-41 much anymore. Production test operators were using it all day to test our product. In fact, the first two million dollars' worth were tested by this HP-41cx and a 20-page program.
Eventually we transfered the control of the production testing to a 68000-based HP series 9000 computer. Interestingly, it was not even twice as fast as the HP-41, because much of the time was spent giving filters time to settle and waiting for readings to come back from the equipment.
I still use the same 41cx every day, but it's pretty seldom that I use it to control anything on the workbench anymore. The 71 gets used more for that-- in fact, that's nearly the only thing I use the 71 for these days-- but that's still not much. My workbench control and data acquisition now is mostly handled by a home-made workbench computer about 5"x7"x2.5".
Edited: 5 Mar 2010, 2:33 p.m.