Flaming Pot--Noob needs help with Beavis Board/LBP-1

[walker]

So I built my own "Beavis Board" using the Breakout Box Graphic from the Beavis Site.   The problem is the I have no way to test if I did it all right.  The LED comes on.  I get lots of hum when I plug it in, whether bypassed or not. with the switch engages there's a lot less hum.     I threw the LBP-1 project on to my bread board.   Plugged in to test, and no signal would come through.   However, when I turned up the Volume Knob, it started a little fire (or a lot of sparks) inside the pot, accompanied by smoke and an awful smell.   Now I don't know if it's the circuit I built wrong, or the wiring inside the breakout box (especially the 3pdt switch).    I'm afraid I fried all the components, and don't want to it  plug in again, in fear of frying more.  

[John Lyons]

Check your wiring. I think you may have accidentally swapped ground for +9v somewhere.
Maybe at the volume pot ground...

John

[walker]

ah, it looks like I had the 1 and 3 pins mixed up on the Voltage Sag Pot.   There's signal now.  The circuit seems to work I guess, but with the Volume Pot all the way up, there's no difference in volume/tone. 


quick question, when looking at a graphic diagram, like this http://www.beavisaudio.com/bboard/images/io_diy.jpg, in regards to the lugs on the 3pdt switch, is it as if you're looking at the switch from a top view or from underneath?  Also, is there a 'correct' direction for mounting, I guess I'm saying which way is up?

[John Lyons]

You probably toasted the pot if you are using the same one that was zapped.
The diagram for everything is as if you are looking into the box from the bottom.
Knob down with the lid off the box...

[walker]

Thanks John.  I think I'm going to just pull everything apart and start over.  I need to wait for new parts in the mail though.  And I just got myself a multimeter, so that should help. 

[walker]

   sigh...   I put the Bazz Fuss circuit on the breadboard.  No signal.  checked all the wiring in the box, checked the parts against the schematic 7 times.  It's just not working.  Still don't know if it's the box or the circuit.   I tried taking the voltage sag out and connecting power directly, still nothing. 

[dano12]

If you could post pictures, it would probably be pretty easy to figure out what is up.

[walker]

I wish I could post pics, but I have no camera or sell phone.

I pulled the entire breakout box apart and started over.  This time trying to be more neat and checking conductivity on every connection as I made them.   Then I put the bazz fuss back on the board.    In bypass there is a lot of hum, but there is strong signal.  With the stomp engaged there is signal, albeit very, very weak.  If I turn the V sag all the way down, it's a little stronger, and picks up some radio station.    Also, when I wiggle some parts around (like the 10k resistor in the bazz fuss) signal gets stronger.   At least I'm not setting things on fire anymore.   

[walker]

Finally a Win!   After several weeks, and a crispy pot, I got my home brewed beavisboard/breakout box working finally, put the LBP-1 on the breadboard and it works!  I thought I'd share while the excitement was still fresh.   I'll have to wait till tomorrow to test it with volume at more then .3 though. 

The big problem? (among several small ones)  Well I'm slightly embarrassed,  but I'll sacrifice myself on the alter of dignity for the sake of possibly helping a fellow noob who might read this.  I mixed up the tips and sleeves of my input and output jacks.  I really wish I could have posted pics, since I know you all would have seen that so quickly.   Special thanks to gaussmarkov.net  for making a completely idiot proof diagram, because I am a complete idiot!     Lots of other great stuff there too. 


Check it...  http://gaussmarkov.net/wordpress/parts/connectors/14-phone-jacks-and-plugs/   

Ok, onward and forward!  Now to get that bazz fuss working...