madbeanpedals::forum

Projects => How Do I? Beginner's Paradise. => Topic started by: baranismen on October 13, 2023, 05:23:31 AM

Title: Adding a pulsating LED for Small Stone
Post by: baranismen on October 13, 2023, 05:23:31 AM
Hey everyone. I wonder how I can implement an LED indicator that'll "pulsate" (not just go on and off) with the LFO of an LM324 & 13600-based Small Stone. The current layout that I have is just goes hard on and off, I'd prefer more of a fading effect if possible.
Title: Re: Adding a pulsating LED for Small Stone
Post by: jwin615 on October 13, 2023, 12:27:26 PM
Do you have the led blinking with the rate already, or just a normal bypass led?
If you already have it blinking, adding a capacitor in series with the led would help it ramp. The size of the cap will determine the speed of the ramp.



Title: Re: Adding a pulsating LED for Small Stone
Post by: NorthCoast on October 13, 2023, 07:10:09 PM
Try this circuit.

Connect "IN from LFO" to the output of the LFO. I'd need to see the layout or schematic to be more specific, but it would be the same place where the 100R resistor connects to the LFO.

R2 sets the LED brightness. You might need to go higher or lower than what is suggested.

The transistor can be any NPN such as 2n3904, 2n5088, etc.

(https://i.imgur.com/5sEjE4E.png)