I've got a 555-timer circuit. When I examine the output-pin on an oscilloscope, I get a nice square wave.
I want to turn an LED on and off, so I've attached an LED and resistor to the output pin (see image, below). However, the LED stays on. When I examine the output pin again, I find a solid signal, rather than a square wave (see images).
If I remove the LED and resistor, and attach the timer-output to GND, I still see the square-wave (I thought perhaps creating the circuit from output -> GND was the issue). I'm not sure how to determine exactly what is happening, or why.
- Why is this occurring?
- How can I modify my circuit to turn the LED on and off?
- What steps could I have taken (before asking here) to further 'debug' my circuit? Using the oscilloscope showed what my issue was, but not why it was occurring.
My wave, before I attach the LED/resistor [sorry for the blurriness]:
When the LED is attached, this is what I get:
Here are some pictures of my breadboard:
When I insert a capacitor (1uF) over the power supply pins: