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  1. D

    Switching DC motor with TIP122 and Arduino

    If you choose MOSFET this would be circuit you would want to use : The diode is to limit L transient that occurs due to MOSFET turn off. Protects MOSFET from exceeding gate oxide rupture. The R18 is to insure when micro starts up, and tristates its GPIO, the MOSFET stays off, until processor...
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    Switching DC motor with TIP122 and Arduino

    Basically these are the conditions you want : So Rb = ( Vout - 2.5 ) / 12 mA Note get Arduino (Atmel CPU, now Microchip) Vout from its datasheet. Note you have 2A flowing thru C-E, whose sat V is ~ 2V @ 3A, thats 6W of power, implies good sized heatsink...
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    Project that was working, but then stopped

    That circuit is a recipie for disaster. First of all the pot can become 0 ohms and tie the base to a 1 V supply causing high current and hose the transistor. You can put a R in series with pot to limit max base current. With no R in series with motor you can possibly burn out the transistor...
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    Watts wrong?

    If you meter has a main rotary function switch its not uncommon, over years of sitting on bench, the contacts get oxidized/corroded a little. Clean that and see if that helps. Contact cleaner helps, if you dont have that pharmacy 90% alcohol works OK. Regards, Dana.
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    Closed loop for two brushless motors

    Consider this : https://static5.arrow.com/pdfs/2010/9/28/18/26/14/882/cyp_/auto/docid23671.pdf https://www.infineon.com/cms/en/product/evaluation-boards/cy8ckit-037/ The above kit is for PSOC 4 but if you port it to PSOC 5LP that has a USBUART in it that is very easy, with example project, to...
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    Nano microchip and circuits

    https://www.google.com/search?q=video+wire+bonding+microchip&rlz=1C1CHBF_enUS999US999&oq=video+wire+bonding+microchip&aqs=chrome..69i57.10311j0j7&sourceid=chrome&ie=UTF-8#fpstate=ive&vld=cid:36e53876,vid:th1YxQHEpEU...
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    Help needed

    Some conversions over here : https://www.youtube.com/results?search_query=skil+convert+nicad+to+lion Revive nicad : https://www.youtube.com/results?search_query=revive+nicad Regards, Dana.
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    First diagnosis steps, how to?

    Generally : 1) Look for hot spots, excessive heat generation, at a component site. 2) Look for solder joint proper wicking on leads and thru hole vias. Magnifying glass great help here. 3) Look for leakage from eletrolyte types of caps, like electrolytics. 4) Bulging caps : 5) Power rails...
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    Small amplifier project power requirements

    9V battery capacity : https://www.duracell.com/wp-content/uploads/2016/03/MN1604_US_CT1.pdf Regards, Dana.
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    Servo motor doesn't go beyond 90 degrees

    Does library run servo - 90 to + 90 ? Regards, Dana.
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    Help with finding an equivalent Mosfet

    Some considerations when picking an alternate : https://electronics.stackexchange.com/questions/573271/what-do-i-have-to-look-for-when-replacing-a-mosfet-with-a-different-model Regards, Dana.
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    How do I find the transfer function of this op amp filter. The negative feedback part confuses me

    Use signal flow graph for manual analysis, or use online tools. Google "signal flow graph analysis", lots of videos, ap notes, etc... https://www.ieee.li/pdf/viewgraphs/analyzing_feedback_systems_with_ignal-flowGraphs.pdf Regards, Dana.
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    Surge protector circuit

    The micro and relay simply too slow for lightning protection. Many resources here (not specifically TV but principles still apply) : http://www.arrl.org/lightning-protection Regards, Dana.
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    Programming LEDs individually

    Here is a simple programmable timer application you might consider : https://www.electro-tech-online.com/articles/pulse-sequence-generator-smart-timer.938/ High power LEDs ? Regards, Dana.
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    Automatic air freshener - timer

    Its the control board that would make that happen. if thats still desired in manual bypass one could think about putting a diode in power line to motor, and another diode that feeds power from a separate path. I am doing too much guessing here. Is the motor for a fan or a positioning servo type...
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    Automatic air freshener - timer

    Just use a DPDT relay, and a switch to turn it on and off, inserted between controller and motor ? Regards, Dana.
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    lowest priority

    https://microcontrollerslab.com/freertos-scheduler-learn-to-configure-scheduling-algorithm/ Regards, Dana.
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    lowest priority

    Depends on the particular RTOS scheduler algorithm. https://www.digikey.com/en/maker/projects/introduction-to-rtos-solution-to-part-3-task-scheduling/8fbb9e0b0eed4279a2dd698f02ce125f https://www.freertos.org/implementation/a00005.html Regards, Dana.
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    define a variable in header file

    Because in foo you keep passing to print the element that you just replaced its value with array[4] ? Regards, Dana.
  20. D

    Looking for more help with my electronic ‘bagpipe’ project...

    Do you have a scope ? If so is it a DSO ? Model # ? A schematic you can post ? Regards, Dana.
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