First detailed Breadboard build. Help with the power.

Fizz

Well-known member
So I've always wanted an OD-1 pedal and thought I'd start with it as my first build. Rather than buy a PCB first and install by numbers I thought I'd try a couple different schematics on a Breadboard and see which I like best before I build it... it should also allow me to actually understand what I am doing a little better.

I've chosen the Yellow Overdrive from BYOC first but I don't understand his power setup. I just want to bring the DC jack straight into the breadboard bypassing the battery/stereo input jack. I guess I still need to build out the filtering section though? I can't figure out where the power is coming from in the schematic? It looks like +V is only going to pin 4 on the IC? Where is the power coming into the power section? I'm also guessing the 1/2v is half voltage coming into the circuit at all the various places from the 1/2v of the power section? Thanks!
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So yes exactly as you said only one spot is getting the full 9V it’s the +v on the op amp. They are using a quad op amp here. It might be easier in your breadboard for use two duals but either would work fine. What I typically do is make my power section either in a seperate small breadboard or in the corner of the breadboard. And run vref to the red power rails and any spot it says 1/2 you’d connect to the red rail and just run a jumper for the one spot you need the +9
 
So yes exactly as you said only one spot is getting the full 9V it’s the +v on the op amp. They are using a quad op amp here. It might be easier in your breadboard for use two duals but either would work fine. What I typically do is make my power section either in a seperate small breadboard or in the corner of the breadboard. And run vref to the red power rails and any spot it says 1/2 you’d connect to the red rail and just run a jumper for the one spot you need the +9
Thanks Locrian! So if I understand what you are saying the +V above can be the same place on the breadboard where the dc comes in and goes to +V (Pin 4) and the rest of the power supply? I'm assuming the +V is still filtered by the rest of the power circuit? I never would have thought about feeding the 1/2 to the red power rails.. great idea!
 
When you build this, do it in stages. Test the circuit after each opamp stage. This way you’ll know where you need to troubleshoot if things go south.
Great advice.. does this mean I need to add R12, C7 and R13 after the first stage and test?
 
Does your breadboard have power and ground on both sides? Like this:
1667680336429.jpeg
If so, I would start with:
1. Connect your power supply + and - to the left side rails.
2. Link the left - blue rail to the right side - blue rail.
3. Build the little voltage splitter / power filter circuit in the top left corner, so that the 1/2 V is connected to the right side - red rail.

That way: both blue rails are ground, the left red is V+ and the right side red is 1/2 V
 
Thanks Locrian! So if I understand what you are saying the +V above can be the same place on the breadboard where the dc comes in and goes to +V (Pin 4) and the rest of the power supply? I'm assuming the +V is still filtered by the rest of the power circuit? I never would have thought about feeding the 1/2 to the red power rails.. great idea!
So how I do it is look at the power filtering section that dot where the 33k, 100u and +v meet I think of a 4 spot there that is 9V in. Pick a strip in the corner of your board or in another board and set up the circuit with your 9V coming in there. Then the +v goes everywhere the +v is called for and the vref goes to the red rail and all spots just connect to the red rail that need vref.

100% agree with buddy at the least give each stage a thorough visual inspection. I’ve fried a mn3207 once because I didn’t do this.

Dans way of doing it works great to.
 
Does your breadboard have power and ground on both sides? Like this:
View attachment 35380
If so, I would start with:
1. Connect your power supply + and - to the left side rails.
2. Link the left - blue rail to the right side - blue rail.
3. Build the little voltage splitter / power filter circuit in the top left corner, so that the 1/2 V is connected to the right side - red rail.

That way: both blue rails are ground, the left red is V+ and the right side red is 1/2 V
Yes it is.. I will definitely try it that way.
 
So how I do it is look at the power filtering section that dot where the 33k, 100u and +v meet I think of a 4 spot there that is 9V in. Pick a strip in the corner of your board or in another board and set up the circuit with your 9V coming in there.
Cool.. that really helps me see it now. Thanks!
 
You all aren't going to believe this... I just started building it this morning following the great advice everyone was kind enough to post. I didn't check anything, I just kept following the schematic above and before I knew it, I was finished. I put it in front of my Ceriatone 2204 which takes pedals extremely well... and the pedal worked! 🥳 Not only that it sounded great. I think it might be the best sounding pedal I have put in front of this amp.
20221106_125703.jpg
 
Nice job! There’s no limit to what you can build now.

The only advice I have is: I’ve been told the pot legs can wear out the breadboard since they are thicker that the jumper pins. So I leave my pots off board and jumper them in with female/male jumpers.
Trim pots work too if you have a screw driver handy.
 

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Nice job! There’s no limit to what you can build now.

The only advice I have is: I’ve been told the pot legs can wear out the breadboard since they are thicker that the jumper pins. So I leave my pots off board and jumper them in with female/male jumpers.
Thanks! Yeah, I need to rig up something like Brian Wampler has so I can mount my pots off board.
 
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