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  1. hevans1944

    Adding filtered signals from the same source

    Yeah, maybe, but of the "points indicated" only one (the junction of C5/R13) is associated with the output. The other two (junction of C8/R16 and R15/C7 don't connect to the output, so "measuring" at those points is meaningless as far as the output is concerned. If you had actually built the...
  2. hevans1944

    how to send signal wirelessly

    Fraught might be the right word, but maybe you should look here to see what is already available. Or just order one from here.
  3. hevans1944

    Stepper motor or Servo?

    Oops! I missed this. One sensor, seventeen vanes of course. I used to work on a wafer holder that had twenty-five positions for four-inch diameter wafers. This was custom-designed and manufactured by a company that has since gone out of that business. But before they cast their design in...
  4. hevans1944

    Convert 110v 60Hz to 230v 50Hz

    @Rabit glad you got some help from people here. If you are still worried about damaging your German apple squeezer, why not send them an e-mail or even write a letter and ask what harm (if any) would come from operating their machine on 220 or 240 VAC, 60 Hz rather than 230 VAC, 50 Hz. As...
  5. hevans1944

    Convert 110v 60Hz to 230v 50Hz

    What number (between 0 and 1) did you enter for the power factor? And where did you get that number? It looks like you entered 230 for the power factor. Power factor is always a number between zero and unity. Click on the power factor link on the page you cited for an explanation. The on-line...
  6. hevans1944

    Stepper motor or Servo?

    Like so many newbies here, you have described a solution (a worm-gear motor driving a plastic disk) instead of describing what you are trying to do. Please tell us what you are trying to do. What determines the size of the "horizontal hamster wheel" and why does it have to have seventeen...
  7. hevans1944

    Stepper motor or Servo?

    Picky, picky. The devil is always in the details. Add an open-collector inverter (or open-collector buffer) as appropriate to how the sensor works and tie all the collectors together for one output. First of the seventeen outputs wired together that goes low stops the motor.
  8. hevans1944

    Stepper motor or Servo?

    I would think you could wire the seventeen sensors in a wired OR fashion so the wheel would stop and brake at each sensor position after a momentary contact closure got it moving, per @Bluejets post #18.
  9. hevans1944

    Piezo element microphone

    I never cared for the falsetto voice of Tiny Tim or his ukulele, but the (now deceased) fat Hawaiian singer, Israel Kamakawiwo'ole ("Iz"), performing Over the Rainbow accompanied by his playing of the ukulele was both moving and tolerable. You can see and hear the one and only first "official"...
  10. hevans1944

    Converting Switch/Case statement in C to ASM?

    No problem, Harald. John has been trying to fit ten kilos of C code into a one kilo memory container... well, less than that with the PIC he's currently using. So I suggested writing some of the C code in assembly to see if that helped. He is using a non-optimizing, free, C compiler, but I doubt...
  11. hevans1944

    Piezo element microphone

    Just what the world needs: an amplified ukulele.
  12. hevans1944

    Converting Switch/Case statement in C to ASM?

    Gee, Harald, I had almost convinced John of the joys of assembler coding and how it would result in more compact code than the C equivalent... :(
  13. hevans1944

    Stepper motor or Servo?

    @Neil-4545 I like the worm-geared motor you picked. You might want to order the stainless steel mounting bracket for it too. And perhaps a flexible shaft coupler between the gear-motor and the horizontal plastic wheel.
  14. hevans1944

    Converting Switch/Case statement in C to ASM?

    I really like the snippet of code you posted from the Microchip forum. Very clever use of the xor statement. The only variable in that code is the value SWITCH which is placed in the accumulator to begin the case tree. The "magic" is the way the assembler preserves the value of SWITCH during...
  15. hevans1944

    Powering an old smoke detector

    According to Wikipedia, it was constructed with "45,000 graphite blocks weighing 400 short tons (360 t) used as a neutron moderator, and was fueled by 6 short tons (5.4 t) of uranium metal and 50 short tons (45 t) of uranium oxide." IIRC, the natural ratio of U235 to U237 and U238 is too small...
  16. hevans1944

    Powering an old smoke detector

    It is not necessary or even possible to build a fission reactor from americium. You need to collect a goodly quantity of yellow-cake or uranium oxide (U3O8) and process it chemically into uranium trioxide (UO3). Then you need to convert, again through a chemical process, the uranium trioxide to...
  17. hevans1944

    Which Microcontrollers to get?

    You are aware of course that once you have used your PC to download a program to the Arduino, you can disconnect the Arduino USB cable and use the Arduino "standalone" as an embedded microprocessor? As @Bluejets mentioned, you can purchase a "clone" Arduino (it is an open-source design) very...
  18. hevans1944

    Powering an old smoke detector

    I have several of these that I salvaged for the alpha source. Years ago we mounted a much more powerful alpha source (it was registered with the AEC) in place of a pen on an analog X-Y plotter. With a clever circuit to drive the plotter in a raster pattern, we measured the current between the...
  19. hevans1944

    Over voltage protection.

    Yep. But since it was free, I had to find something I could use it for, just to justify the labor of lugging it home. I had some slotted angle-iron and plenty of bolts and nuts handy, so I cobbled together a "frame" for it and added four smallish wheels and a bungee cord to drag it around the...
  20. hevans1944

    Best cheap material for diy low power heating element

    Thanks for the vote of confidence, @Bluejets. I am not going to add any more here because I prefer to respond to posts that actually use punctuation (commas, periods, etc.) and an appropriate mix of upper-case and lower case letters. Life is short: eat dessert first. This should be a new thread...
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