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Dual Astable 555 Timer

The 555 which comes in a number of technology variants (Bipolar & CMOS), single, dual elements and different package styles (SMD & DIL), and finds many uses in a variety of applications from timers, pulse generation and oscillators.
All of these applications have one thing in common and that is a single output on pin 3 which can both source and sink current.
A typical use for the 555 is as an Astable Oscillator with the 2 resistors version being the most referenced allowing duty cycle adjusting by the ratio of these 2 resistors.However, there is an alternative and simpler single resistor version if a ~50% duty cycle will suffice. By utilising this simpler version we can turn a single output Astable into a two output Astable Oscillator. So how is this achieved.
555 Timer
LED’s x 2
220R resistors x 2
470k resistor.
1uF/16V Electrolytic Capacitor
100nF ceramic Capacitor
20 AWG Enamelled copper wire
22 AWG Enamelled copper wire
Needle files or other tools to remove the enamel to enable soldering.”

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