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I'm working on a tube amp project and I need to order some 1/2 watt pots for it but I'm having a hard time finding them.
Does anyone know a good source for 1/2 watt or more pots?

I tried Mouser.com but by the time I filter for audio taper and the resistance I need and the only ones left are not stocked.

I'm looking for 250k and 1M pots for the pre,gain,treble, and bass pots.

Thanks.

I have one of those mics. I used to use it to record band practices. It sounds pretty good and with the level control on the mic you can record in a really loud room without it distorting.

I can't tell from the pics. Did you leave R31 off? If not what value did you end up using?
The specs say 470k but then say you could try increasing to 680k or 750k ...

I haven't boxed mine up yet and I left R31 off. I think I'll put some sockets on it to test different values.

I built one of these last night.

Red and Black are power and ground.
Yellow is input.
Green is output.
and the testing probe.

I repurposed an old 'confidence booster' pedal. One of the first I made.

Only thing I messed up was putting the input on the left side of the pedal and the output on the right.
I thought it wasn't working at first until I figured that out.

Once I had it plugged in correctly it works great.

I just finished building the Zero Point DD. I had tried to test it on a bread board but was getting weird static noises if I turned my guitar down from full volume. Once I tested it with this rig I have no problems at all. Sounds great.

I have a few questions about the DD but I'll make some recordings and start another post about that. (I've already seen there are some other mods people suggest that are not in the build specs.)

Here is my Sparkplug build. I spent 1/2 hour trying to get the pictures correct but they keep coming out sideways. If you right click and open in a new browser tab you can see them in the correct orientation.

I used an extra nut on the DC jack (on the outside) so I could get the space I needed for the two switches.

Just curious what do people normally do so that the input and output jacks don't stick out so far. Am I just buying the wrong ones?

I really like the sound of this pedal. Mostly I keep the presence and saturations switches on and don't do much with the cut switch. I haven't played around with the trimpots yet.

I should have used knobs that have the index on top. I would be easier to see where it's set. I had to get very skinny knobs because of the switches in between.

Nice, I just finished one of these myself. Need to get pics up soon. Really like this pedal.

Cool, Thanks.

Hopefully I'll get this put together tonight.

I'm putting the Spark Plug together and it's the first build I'm doing with the LED circuitry on the PCB.
http://www.madbeanpedals.com/projects/Sparkplug/Sparkplug_rev1.pdf

My LED is going to have to be wired up (rather than soldered directly to the PCB). I'm a little confused about how to wire it. do I wire the positive end of the LED to the square 'LED' hole on the PCB and then wire the negative end of the LED to the top left post on the 3PDT switch?

Do I just not use the Ground hole on the PCB next to the square LED hole, or do I have to wire the negative end of the LED to both the ground next to the LED and to the top left lug on the switch?

I'm using the basic wiring diagram for wiring my switch.
http://www.madbeanpedals.com/tutorials/downloads/StandardWiring_MBP.pdf

the basic wiring diagram says if the board has LED on it to "connect the 'sw' pad from the PCB to the top left lug on the 3PDT instead" but I'm not sure what they mean by the 'sw' pad.

Thanks.

I just found this and it looks interesting. I haven't tried to build any of my own circuits but this would be a great tool for creating schematics and trying different values.

I looks like the free version is a limited trial and then there are three levels of membership at $40, $65, or $200 per year depending on the features you want.

Schematic editor and circuit simulator.
Build and test circuits right in your browser!

* Design with our easy-to-use schematic editor.
* Accurate analysis (DC, AC & more) in seconds.
* Beautiful schematic printouts (PDF) and images (PNG).
* Share a live circuit URL so others can simulate and edit your circuit.

https://www.circuitlab.com/

Cool, Thanks.

I'll check those out.

I might just order a new pcb and start over with this pedal. Seems like every time I use it something else strange happens.

Hi,

I built the Cupcake pedal and I've had a few problems I had to fix.

I had a solder bridge on the drain and source of Q1. The only way to get at it was to remove the trimmer pot and the Q1 transistor (it was on the component side of the board under the body of the transistor). I put in a new transistor and a new trimmer pot (I destroyed both trying to de-solder them).

Since then everything seems to be working but I've noticed a strange modulation or tremolo effect that is just barely noticeable when notes ring out.

I'm wondering what the most likely cause of this is?

I'm guessing that it can only be a transistor or the IC. 

I build a Cupcake and I've read that the Sus trimmer pot should read about 1.5 - 1.7 vdc to get compression without it turning into a boost.

If that's the case, then why do they have a 10k trimmer pot?

Wouldn't a 5k or 3k trimmer pot be a lot easier to dial into the sweet spot?

This is the first real pedal I've built and I'm just curious why you would pick a pot with such a wide range when the useful range is so small in comparison. On the pot that I have the useful range is about 1/2mm in one direction or the other.

Here are some pics. I guess my drill slipped when I was drilling the pilot holes so the level pot is a little off center.

I was going to put an orange led on it (ended up using red) but when I received them I found I had ordered tiny LED's that were about half the normal size and didn't fit in the bezel I had.

I'm still waiting for some knobs to arrive.

One question:

In the blog I linked to above it had a bit about measuring the voltage of the trim pot.

"...the schematic shows an arrow pointing to the place where the trimpot, 24k resistor, 4u7 cap and gate of the secondary FET are tied to the source of the principle FET. The schematic indicates that, with a 9v supply, this trimpot should be adjusted to read between +1.5 and +1.7 vdc. Obviously you can take that reading at any of the aforementioned components where your probe conveniently fits."

Where on the board would I take those measurements? (I have the 05.2012 version of the PCB)

Thanks.

I just built my first Madbean pedal, the Cupcake Orange Squeezer compressor.

I noticed that on the pcb there are outlines of the components and some of the capacitors are square while others are oval shaped.

For example C1 and C2 are both listed as 47n but C1 is shown as square and C2 is oval.

Should I have bought different types of caps for those two? Do the shapes indicate different types of caps?

Thanks.

P.S. The pedal sounds great. I thought I had done something wrong when I first tried it but I just had to adjust the trim pot correctly. 

I got some great help from this blog about the pedal and the trim pot.
http://www.jurimusic.com/2013/06/the-madbean-cupcake-diy-orange-squeezer.html