Andy 40's Madbean Snarkdoodle (Overdrive Pedal)

[Andy40]

Tried different caps and resistors, earthing it to breadboard. nothing really worked, some of it made it worse. It may be an issue with the circuit being open on the breadboard.

I've moved on to double check the PCB with the multimeter and populate the pcb!!!

Quick question though as you can see on the silk screen I can identify, G for ground, In and Out and the LED....but what is "L"? its got me stumpted

[DrNomis_44]

Tried different caps and resistors, earthing it to breadboard. nothing really worked, some of it made it worse. It may be an issue with the circuit being open on the breadboard.

I've moved on to double check the PCB with the multimeter and populate the pcb!!!

Quick question though as you can see on the silk screen I can identify, G for ground, In and Out and the LED....but what is "L"? its got me stumpted

I just had a look at the circuit diagram and the pad marked "L" goes to the cathode lead of the Led, so, I think that pad marked "L" is where you solder a piece of wire that goes to the footswitch so that it turns the Led off when you stomp on the footswitch to bypass the effect.

[Andy40]

Thanks doc!

[DrNomis_44]

No worries mate.

[mjg]

Yep, the 'L' pad is the one that you connect with wire to the 3rd pole of the foot switch. It's done that way on all the Madbean PCBs that I've seen.

The LED itself goes into the '+ LED '-' pads.

Note that R7 is the current limiting resistor for the LED, and depending on what colour LED and how bright you want it, you may need to adjust that resistor value. If you've got one of those super bright white or blue LEDs, you will probably want a higher resistor value in R7. I'd double check your LED and R7 on breadboard before committing to soldering that one in. Speaking from experience... I've made that mistake more than once.

[DrNomis_44]

If you're running your Snarkdoodle off a 9V battery, and you decide to use a high-brightness Blue Led as the indicator, then a suitable resistor value for R7 could be anything from say 22k to something like 56k, personally, I got pretty good results using a 47k current limiting resistor with the Blue Leds in my pedal builds that run on a 9V battery.

[Andy40]

As its a red pedal (and I don't gig, I'll probably use a high Red LED. (I managed to blow my last one testing the pedal).

Here's what i got up to today..


Poured multiple cups of coffee and tested the circuit with a multimeter (couple of faults - not bad) - fixed faults

Populated the board and soldered it up (a few boo boos) best damn soldering job i think i've ever done!.

Rocked it before i boxed it!



Drilled most of the enclosure in a 1590G



Put it together....



Thats it till next time folks.....

[mjg]

Looks good!

How did you find the sound once you got it on the PCB?

[DrNomis_44]

Looking good there mate, so I'm assuming that you're going to be spray-painting the pedal a Red colour then?


I finally got all the electronics in my Gold strat all working a few minutes ago, all the new Kent Armstrong Dual-Blades appear to be working, as does all the controls, I just need to wait till next week to buy some strings so I can string the guitar up, set it up, and then do a demo of it.

[stan]

It's coming together nicely Andy - cant wait to hear the result