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Binary Clock-LED not working, why? Answered

I followed about everything on this plan https://www.instructables.com/image/FZQILLUFIM95W1L/Schematic-And-Parts.jpg

But Instead I used a 555 in astable to run about 1Hz. I already tested the 555 on a individual led and it worked.

Now I finally completed my work and my leds are not lighting up. I believe I should remove the resistor since the max output of the counter is only about 4mA so I would be limiting my current, ALOT.

The thing is, I tested every LEDS with a multimeter both including resistors and not and they are all lighting up all fine, but when I install my counter, see that the led are not working and I try to make a diode test, they doesn't light up at all.

I need to remove the counter in order to be able to light them up.
What is the solution and why?
Is it sinking current? But it design is not to sink, but to source.....

Help please, thanks.


If the current sourcing is where your problem lies, have you thought of using a buffer IC or an array of discrete transistors?

I would be strongly inclined not to remove the protection resistors or you may potentially damage both the counters and the LEDs.

Also, if there is no current getting through, have you performed a continuity test between the two power rails (with no power supply connected of course) to check for a short circuit?

9 volt battery.

I used the instructable over https://www.instructables.com/id/Binary-Clock/

and aparently its supposed to work. The only difference I made is use a 9 volt battery instead of a unregulated power suply.

But that doesn't explain why my led won't even turn on when trying to make a diode test while the counter is connected, with power or not, they dont light up.

Is the counter outputting 9V on any pins when you try it, or is it still in reset ? 

Its a sloppy circuit. Are you running it on 9V.

I can't read the diagram to identify the parts. The resistors protect the chip, which you say can only source 4mA. I'd suggest the leds need more current than the chip can provide.