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    DC motor speed control.

    Hi again, I have swapped the base R for a 100ohm and that’s working fine. To answer you’re question, yes I was measuring the voltage directly across the motor. You will have to forgive me as some of your code suggestions are going over my head, but yes I’m open to learning some basic. another...
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    DC motor speed control.

    Hello Alan, I have the BD139 (in place of the FET) with a 330ohm R on the base as you suggested. Along with the code you supplied. Again I have some interesting results to share. First off your code in combination with the IRFZ44N didn't work at all, howeve once I swapped the FET for a BD139...
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    DC motor speed control.

    What do you mean by flowchart not supporting PWM outputs? The FET is not hot at all, but isn't logic level as pointed out before. I have a BD139, a BC550B, a BC547. I was also able to find a 40n03gp MOSFET as well as a p60nf06 MOSFET if they are any better? Don't know enough about...
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    DC motor speed control.

    I know that FET isn't ideal, but its the only FET I had on hand. its attached to a heat sink and isn't getting hot to touch but you might be right about the under power issue. I guess the only way i'll know for sure is to get a different one. The schematic calls for an IRL520.
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    DC motor speed control.

    Just tried swapping ADC_C.0 for VarA but that works even worse. Motor barely rotates at all.
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    DC motor speed control.

    The image files were too big before, fixed now I hope, plf there too. Thanks heaps.
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    DC motor speed control.

    Not sure if the images attached properly
  8. B

    DC motor speed control.

    Hi, I have tested my speed control circuit with interesting results. Here is the circuit I built up including a ceramic cap (104) across the motor as Buzby suggested. I am using a perfectly regulated 5V from a 8.4V Lipo through an LM7805 for my initial tests. I have got my 10K pot connected to...
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    DC motor speed control.

    Thanks heaps for the detailed explanation. I will try it out later and let you know how I get on. Billy.
  10. B

    DC motor speed control.

    Hi guys, I have a small DC motor which I want to control the speed of using a 10K pot as an input. I would normally go about this by using a 555 timer circuit, but we are in lockdown at the moment and I don’t have any on hand. My idea is to use the 14m2 that I have and PWM control to control...
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