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  • Author Author: Jan Cumps
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Working with Modest Equipment

Jan Cumps

You'll see in my blogs that I don't use state-of-the art lab equipment.

That may point out that I'm a cheapskate. And yes, that's part of the story.

But the real reason is that I believe in modest means. I've learned that during my electronics studies.

 

I learned electronics in the 1st half of the 80's, when two things were different from now. Lab equipment was much more expensive. And there was a big crisis.

These days, I can afford to purchase a +100MHz, 4 channel oscilloscope, even mixed signal if I stress my budget a little. But I don't do that. I use a second hand DS1052E.

And I believe that my education learned me a great thing: learn to design and work with tolerance, fault margins and uncertainty.

 

Tolerance

I like to think that that is the best thing I got out of my education. Try to design with the worst component possible. Make a stable design with 10% tolerance. Use transistors with high Hfe range.

Deal with the real world at its worst.

 

These things force you to get a deep understanding of the problem domain. Almost an organic understanding.

 

The same with meters and other lab gear. When you have high-end material, it's easy to replicate tests.
When you deal with modest means, the brain has to jump in. You learn.

If you find yourself in a situation where your test gear isn't optimal, you have several choices.
The two most popular ones are:

  • give up or
  • think further.

When you choose #2, you learn. You understand and grow.

 

 

You'll often see articles from me where I use a mediocre meter, or where the signal on my oscilloscope shows significant ringing. That's my own choise. I like to go for the core of the problem.

I'm not looking for perfect images. I want to see that my design works. Or I want to see what happens in a circuit.

If precision is not part of the problem domain - I ignore it and don't take measures to avoid it. If the integrity of the signal does interest me, I use better measurement methods.

Or I visit a friend with better gear - something I plan to do again soon. I will keep you posted on that image.

  • in reply to D_Hersey

    It took me a while to answer this one. Maybe because I like to argue more than to agree?

     

    In those cases where I have to see changes in measurements, I often fold back to an analog multimeter.

    It may be my age. I learned electronics in the first part of the 80's, and my (everyone in my class's) tool of choice was an analog meter.

    We spent many lab sessions learning how to use them accurately and correctly.

     

    I have switch over to digital for anything where I have to get a measurement. It's so easy to read the digits, and you can't beat the performance of a good DMM.

    But whenever I want to see a signal rising or falling, I fall back to the analog meter - it's still the same one from the early 80's.

    It's more intuitive to me than the bar graph display in the DMMs. I can commit my brain power to the problem at hand. My intuition deals with what the meter says in parallel.

    I have no issues interpreting the DMM, but it takes brain power away from my in-circuit thinking....

  • It is not the instruments that make accuracy, it is the attention to detail during your experiments.

     

    They teach error analysis for a reason.  It allows you to assess your results within the limits of your instrumentation.

     

    This problem is why Heisenberg failed to come to the correct answer about the electron cloud around atoms.  His data told him that the charges within the cloud were quite small and uniform, but he incorrectly concluded that he could not find the electron because his measurement instrumentation affected the electron position.

     

    My own analysis of his experiment provided me with a different conclusion which is more consistent with other observations about the electron cloud and clarifies the relationship between the atom nucleus and the electron cloud.

     

    DAB

  • in reply to tomaja

    I'd used that arrow but hadn't realized it was context-sensitive and includes the 'Like' when reading a post - awesome : )

  • in reply to shabaz

    I have some actions available when I click this arrow:

    Rm3qNOW.jpg