I have a little circuit wired up and working using the schematic on this page:
http://www.circuitbasics.com/555-timer-basics-bistable-mode/It works fine for showing the state of an associated device when powered up with a battery; powered with anything from 6 volt to 12 volts.
However, I want to power it up using a suitable power supply from the mains (240volt).
I've salvaged a capacitor (transformerless) power supply out of another device given to me for the purpose (not sure what it is). This puts out 12 volts.
When I power my flip/flop with this, it will illuminate the main LED, but will not reset when I press the reset switch. I just reverts to the first LED.
I assume that the output is not clean enough ie: has too much ripple to allow the timer to function as designed.
Corrections in this regard invited please?
Secondly, what is an alternative power supply that will be clean enough?
I have a very small output transformer that has a primary impedance of 1k which I might try to use in a transformer, full bridge rectified, electrolytic cap smoothed power supply. I don't know if this will work or not?
Is someone willing to provide some advice and tips here please?
Jim.
Edit: I have found a recycled USB power supply that will run this unit at around 5.2 volts. However, I would like a 6.6/6.8 volts supply in order to supply a float charge to a LiFe backup battery ( 2x 3.3 volt cells).