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    need to get rid of oscillating voltage...

    the input im using for transistor inverter is constantaly oscillating from 1 to 3 volts i need to get it to 0....cause im using the transistors output for a 555 timer, since its oscillating the timer keeps going off
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    piezo buzzer using 555 ?

    Ok. Help me out here , i read on the forum the explanation on a voltage divider . Since the value of the resistence on the lower one is 100 , it takes less voltage to make the electrons flow , so since the less voltage is required it means that less voltage is flowing trough Vout, what i still...
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    piezo buzzer using 555 ?

    Thanks for your patience , ill let you know tomorrow...
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    piezo buzzer using 555 ?

    remember im new at this, would these changes in resistors make the transistor less vulnerable to voltage fluctuations, cause as i understand the base needs to be low at all times, so i need a way to stop the fluctuation at the base , how would i go about it, im sorry  to be a nagg but i really...
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    piezo buzzer using 555 ?

    Everythings is ready and tested , works great , dont know how to thank you !!! Keep up the good work u sure are THE GURU!!!!! But i think ill have to tap the signal from the ecu directly to see if i can get a cleaner signal , cause on the locks it oscillates betwen 0.2 and 2.12 volts , making...
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    piezo buzzer using 555 ?

    DONE!!!!! monostable done , with a 2 second "ON" time. All i need now is to make the transistor inverter , correct me if im wrong , but wouldnt that be 12v (resistor ) to base , and grond to the collector , so when the base glows, allows a path to ground?
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    piezo buzzer using 555 ?

    U DA MAN, i was reading on monostables i figured that was what i need it, but u beat me to the punch , so here it  goes : Pulse from the locks , to trigger the timer , 555 using an constant 12 v from the accesory or near voltage supply on the car . 1- Timing calculator for the buzzer? . 2-...
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    piezo buzzer using 555 ?

    Went and got a pulsating buzzer from radio shack , i could use the momentary voltage to the lock solenoid to somehow activate a flip- flop that is power independently from a 12 v source , so when the voltage is applied for a second or so to the flip-flop it could activate it cuont the time and...
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    piezo buzzer using 555 ?

    any help with the schematics? do i need to have a constant supply of voltage or could short pulse do the job with a cap?
  10. T

    piezo buzzer using 555 ?

    How about using the signal from the keyless ecu, that sends a momentary 12v to the locks I could use that to trigger it , the problem is that im so new at this , and  i have a lot of questions.... use the signal from the ecu with a diode , to trigger the oscillator, which in terms causes the...
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    piezo buzzer using 555 ?

    Thanks man, correct me if im wrong , ill be using the led to trigger the counter , it would start the sequence, drive the beeper trough a transistor and stop, does it mater that the led would be pulsating as long as the car is locked or would go into a loop aqnd reset itself everytime the led...
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    piezo buzzer using 555 ?

    High guys im a n00b at this, but i've been practicing a lot , i need some assistance on a project , when i use my keyless entry on my car it doesnt emit any sound or visual alert so i dont know if its open or not . i want to use the light from the security led to trigger my 555 so it can emit 3...
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