Author Topic: Rullywow Vapor Ray (Jan Ray Clone) LED Not Working  (Read 1151 times)


Rullywow Vapor Ray (Jan Ray Clone) LED Not Working
« on: May 30, 2017, 11:45:05 AM »
I just completed a Rullywow Vapor Ray (Jan Ray clone) build, and everything is working as it should except the LED is not working. This is the exact opposite problem that I usually have, where the LED is the only thing that's working!

I noticed that at the bottom of the main pcb there is a pad marked LED, but I've seen a couple other builds of this pedal where they had no connections to it.

I thought I had everything wired up appropriately. The pedal produces the desired effect when the stomp is engaged, so it's clearly getting power. I measured the voltage at the LED and the anode is getting a little under 9V (main is about 9.5V) and the cathode is getting around 7.5V. I've never measured voltage at the LED before so I don't know what to compare it to. But I thought the cathode of an LED would be 0V? Or maybe not, cause an LED is a voltage drop component...?


Re: Rullywow Vapor Ray (Jan Ray Clone) LED Not Working
« Reply #1 on: May 30, 2017, 01:09:37 PM »
According to the schematic the LED pad is the cathode of the LED this is supposed to be connected to the switch and the switch then connects it to ground when the pedal is engaged, which turns the LED on. So you need to add a wire from the LED pad on the the board to one of the LED cathode pads on the stomp switch board, I think they're the pads with the white square round them.

By the way I don't think you need the twisted together red and green wires coming from the side of the switch board, look like they're going to the power pads at the top of the main board but the red and green wires from the top of the switch board are already sending power to the main PCB.
« Last Edit: May 30, 2017, 01:17:23 PM by slacker »


Re: Rullywow Vapor Ray (Jan Ray Clone) LED Not Working
« Reply #2 on: May 31, 2017, 10:25:35 AM »
Hey Slacker - that did the trick (connecting the LED cathode pad on the breakout board to the LED pad on the main board).

Thank you very much!


Re: Rullywow Vapor Ray (Jan Ray Clone) LED Not Working
« Reply #3 on: October 04, 2021, 01:04:27 AM »

I was having the same issue, so I found this and it solved the problem but I noticed that after the first time I connected the PCBs LED pad to the negative LED pad on the breakout board, it turned the LED on and kept it working even after I removed the alligator clips that I originally connected it with. Why would it remain active even after I removed the connection?