simple 555 timer circuit, driving me mad

I'm not a newcomer to electronics but I'm a newcomer to ICs and thought I'd try a 555 timer to flash a LED.

I've tried this over and over again - the LED just comes on and stays on.

I've recently recreated the circuit in a simulation program and the same happens.

Please- what stupid thing am I doing wrong?

Thank you.

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Try to lower the 470k

Try to lower the 470k resistor. It is a very high value for that 1uF capacitor. Try using something like 10-100k and try again.

Joined February 12, 2018 696
Monday at 02:11 PM

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