Im building a simple 10 step analog sequencer with a 4017 decade counter
below is an extracted circuit of a step indicating LED for a single step of the sequencer,
I need to indicate 3 things with the LED
off -step inactive
on, dim -step active, gate off
on, bright - step active, gate on
what i need help with is getting the 2 different brightnesses.
my schematic shows a simplfied version of an active step,
a transistor before the LED triggered by the 4017 will dictate whether a step is active in the full circuit.
the pulse from the 555 is the gate, as you can see it has less resistive pathway to LED so it will give the brighter glow,
when the pulse is over the lower current signal directly from the supply would need to 'take over' to leave a dimmer LED.
I feel this circuit in its current form wouldnt work properly due to low current signal being connected at the same time as the higher current signal from the 555, how would they effect each other when connected simultaneously?
I have briefly tested this with strange results but i want to inquire here to actual find out what will be going on electronically

below is an extracted circuit of a step indicating LED for a single step of the sequencer,
I need to indicate 3 things with the LED
off -step inactive
on, dim -step active, gate off
on, bright - step active, gate on
what i need help with is getting the 2 different brightnesses.
my schematic shows a simplfied version of an active step,
a transistor before the LED triggered by the 4017 will dictate whether a step is active in the full circuit.
the pulse from the 555 is the gate, as you can see it has less resistive pathway to LED so it will give the brighter glow,
when the pulse is over the lower current signal directly from the supply would need to 'take over' to leave a dimmer LED.
I feel this circuit in its current form wouldnt work properly due to low current signal being connected at the same time as the higher current signal from the 555, how would they effect each other when connected simultaneously?
I have briefly tested this with strange results but i want to inquire here to actual find out what will be going on electronically

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