New answers tagged 555
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Sign Modulator - Class Project
The output of the LM311 must be wired to Vcc through a pullup resistor of 2 kΩ.
The EMIT OUT pin must be wired to ground.
Two pins of the timer 555 must be wired:
RST (pin 4 to VCC) and ...
CONT (...
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NE555 + CD4017 Airplane Strobe Light with LDR
Other answers have noted the problem, but I'd suggest an alternative solution: have the right side of the LDR connect to Q8 of the 4017 rather than VDD. That would ensure that no matter where during ...
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NE555 + CD4017 Airplane Strobe Light with LDR
The LED is getting stuck on because you're not also resetting the CD4017.
- 170k
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NE555 + CD4017 Airplane Strobe Light with LDR
There should be a pull-up resistor (say 10k) between the 555's Reset (pin 4) and Vcc.
Also add a decoupling capacitor (4.7uF) between Vcc and ground close to the 555's pins 1 and 8.
You need to hold ...
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Motor Driver Project using 555 Timer PWM + 4N25 + 2N7000
Power source: two 12V dc, 450mA power supplies
Oh, that's interesting! It means your supply is inherently supplying less current than your motor might be able to sink.
This is relevant in this ...
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How to boost the output voltage of my 555 timer design?
The circuit with the 555 cannot apply more voltage than the power supply to the piezo buzzer. So it will be less loud than if you connect it directly across the battery.
The circuit you show would ...
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switching off 555 timer with trigger button
Here is an idea that manipulates the switching threshold point, by the D-type flip-flop, to terminate the timing cycle early. D1 is used as a low reverse-leakage diode with 2.2 V forward drop.
Circuit ...
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555 delay timer before powering PCB with 5 V
That's not how a 555 timer works at all. Your description of the circuit is incorrect and the circuit itself is incorrect.
The 51K resistor does not go to ground as you say, it goes to the trigger ...
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Monostable "One shot" 555. Longer trigger than T (output pulse width) eliminator
This can also be built with 2 transistors, a capacitor and a few resistors.
An example a bit down in the forums here (only a breadboard overview, note one superfluos resistor, and the rightmost ...
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