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    can a pwm create a radio wave?

    hi! correct me if am wrong... if i have a circuit:  a DC power supply 5v, to turn ON a simple led and a switch, when i press the switch it will turn the led ON and it will create a radio wave...? soo... simply turning a device on and off many times will produce radio waves?! if i make an...
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    alarm circuit issue

    hello!!! i made a alarm circuit with a fototransistor and ir led , when the door opens it turns ON and a siren HIGH sound activates and the only way to turn it off is manually…. anyway it works great! but when the power supply ( a 3.5 v battery ) is On for about 7 hours, it automatically turns...
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    how does a PULSE code MODULATION WORKS?

    how does a PULSE code MODULATION WORKS? When I press a button in my IR transmitter it will send binary codes example. 1 1 1 0 with a 38 KHZ carrier. The IR receiver device will detect the 38 KHZ ( with the filtered code, 1 1 1 0) and will let it pass. BUT… how does the device know where to...
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    my transistor gets hot, line follower/dark sensor

    hi! i have almost made a line following car (toy) but i have 1 problem.... my transistor gets hot after a while... am using about 7 volts power supply, i have 2 transistor as a darlingon " bc337 transistors "( when i put the light off the dc motor run very fast like i want ) but when i touch...
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    i need a multichannel infrared control

    hi i need a  multichannel infrared control, about 4-5 channels, transmitter and emisor I have 2  ic 555 chips  and 1  t74ls00 chip. thanks
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    i need help for pic programming...

    hi! i dont have a serial port neither a printer port in my desktop, ( i want to program my pic16f84 ) i dont want to buy a pickit stuff. so what if i buy a "pci serial port" will my diy programmer work?
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