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    12v regulator / voltage limiter

    This is a simple approach, not as efficient, as using buck / boost. For future reference, driving constant current, so T and V effects always yield the same current thru LEDs. Needless to say LM317 has to be heatsunk. Note the series V of the 3 LEDs, each 2V in this sim, limit low voltage part...
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    Make a 74LS193 Synchronous Down Counter Stop at Zero

    Right now you have a divider, so it runs continuously. One way is to detect 0, the falling edge of the borrow output use that to stop clock or clk a D to force the counter to hold its CLR input active. And use the load signal to clear that D.....and restart counter. Regards, Dana.
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    Using mosfet to switch 12V to a load with a hard ground.

    SSR ? https://www.banggood.com/SSR-25DD-or-40DD-DC-Control-DC-SSR-White-Shell-Single-Phase-Solid-State-Relay-p-1975868.html?cur_warehouse=CN&ID=6321349&rmmds=search Regards, Dana.
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    Using mosfet to switch 12V to a load with a hard ground.

    If you are stuck with one side horn grounded then you do a high side switch. https://www.vishay.com/docs/70611/70611.pdf https://hackaday.com/2015/09/16/learn-and-build-a-high-side-switch/ https://www.baldengineer.com/p-channel-mosfet-tutorial-with-only-positive-voltages.html Regards, Dana.
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    Newby question - Yaesu FT-757gx

    Does that transceiver switch to a different LO for the higher bands ? And if so thats crapped out ? Or a different PLL ? Regards, Dana.
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    Barking activated device/alarm??? DESPERATE!

    Not sure this would work but how about a positive reinforcement approach. If they dont bark over a period of time they get rewarded, If they do bark no treats for some length of time. Use this in conjunction with small lights or LEDs, a treat is coming, if they bark reset system and start over...
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    Question on Stepper Motor Won't Reverse

    Can you see with scope the dir pin is being flipped ? The level converter, its has to supply, worst case, 16 mA for each pulled up pin, eg, ENA, OPTO, PULL, DIR, so confirm its able to meet their high level requirements. Note when you post code use the code tag menu item, it makes the code...
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    Calculate the transfer function of an OPAMP circuit

    If input to an integrator is left unconnected it will integrate its own bias current, so you will see a ramp, can be either + or - going ramp, until the output of the integrator saturates, either close to + supply V or its - supply V. Regards, Dana.
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    Calculate the transfer function of an OPAMP circuit

    Signal Flow Graph to get at T(s). https://eng.libretexts.org/Bookshelves/Electrical_Engineering/Electronics/Microwave_and_RF_Design_III_-_Networks_(Steer)/03%3A_Chapter_3/3.02%3A_Section_2- https://github.com/ahmedkotb/sfg.js?tab=readme-ov-file...
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    My controller outputs square waveforms in 5 volts PWM SIGNAL. I want to change the waveforms into current waveforms with some circuits.

    Here is the load R swept from 1 ohm to 500, with Vin @ 5V : Current only changed by 35 uA. Regards, Dana.
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    My controller outputs square waveforms in 5 volts PWM SIGNAL. I want to change the waveforms into current waveforms with some circuits.

    What is the OpAmp supply V value ? Desired range of input V to OpAmp ? Keep in mind Iload = Vinopamp / RS, so 10 mA thru .25 Ohms says Vin to opamp has to be 2.5 mV which the OpAmp has 2 mV typical of offset. If you want 0 - 5V in = 0 - 10 mA load then RS must be ~500 ohms. The above sims...
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    My controller outputs square waveforms in 5 volts PWM SIGNAL. I want to change the waveforms into current waveforms with some circuits.

    A simple method is to use a low pass filter on PWM output producing a V proportional to PWM duty cycle, and feed that to a V to I converter. There is a latency associated with this approach, how much time from a step change from 0 to 10 mA can you live with ...
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    Sallen Key Low Pass Filter, bandpass filter

    I have not read this entire thread but hanging 10 uF and 100 uF on the output to ground I would think ill advised due to stability issues..... Regards, Dana.
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    .5 delay with a 555 timer

    These might help, attached. Regards, Dana.
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    3.5 digit LCD IC - faulty multimeter (NJU9203)

    Some info here : https://www.datasheetq.com/pdf-html/534547/JRC/3page/NJU9203.html?lang=en You can look at data lines to see if the LCD is being muxed. Regards, Dana.
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    Science fair electromagnet suggestions

    Most low cost Clamp meters current measurement good for AC, not DC current. Check your meter manual. Low costs ammeters : https://www.banggood.com/search/ammeter-digital.html Regards, Dana.
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    I want to make a speed limiter for my motorcycle

    Correct ! Or a GPS solution.....or a radar solution....or a ....... Of course one could solve that with even clutch removing engine state involvement..... Braking control..... Post 46 is just ideas one could consider. One could even release a parachute if bike flying off cliff (like the...
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    I want to make a speed limiter for my motorcycle

    What would your concerns be if it was a speed limiter and a rpm limiter, taking into account tire size, etc.... ? Seems sensible to me, go cart tracks for wannabe consumers do that. Been doing engines since 1800's.... So op would have to also detect tire revs, coupled with...
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    I want to make a speed limiter for my motorcycle

    Post # 24 is way to go becuse you avoid the HV of spark plug wire. Do you have a scope so you can look at signal from crank sensor that goes to CDI to trigger the spark ? Note whatever way you do this you can use rate of change sensing in code to see if RPM is going to become excessive even...
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    Sallen Key Low Pass Filter, bandpass filter

    Page 36 of https://www.ti.com/lit/ds/symlink/tl074.pdf?ts=1710167213287&ref_url=https%253A%252F%252Fwww.mouser.com%252F
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