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DIY Stompboxes => Building your own stompbox => Topic started by: stratking on September 23, 2003, 02:24:04 AM

Title: Can someone look at this and tell me what I'm doing wrong?
Post by: stratking on September 23, 2003, 02:24:04 AM
Hey all, I am trying to finish up my first stompbox but am getting nowhere.  When I get everything all wired up and plugged in I get no sound.  When I try the circuit w/ the volume pot wired up all I get is a lot of bad static so I decided to make everything simplier but just taking the vol. pot out and and wiring the input and output straight to the board, now I get nothing.  I am following this schmatic http://www.geocities.com/CollegePark/Library/1355/electra.gif off of the effectronics site.  Sorry if the pictures don't tell too much info, didn't know what you guys need to see and was just borrowing the camera.

http://student.claytonstate.net/~csu18796/SB1
http://student.claytonstate.net/~csu18796/SB2

Oh, and the only reason I haven't trimmed the leads yet is because this is the 4th board I had to make and kept trimming the leads too short to be able to use again, so this time I am just leaving them until I get everything working.


Thanks,

stratking
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: Samuel on September 23, 2003, 02:50:27 AM
Hard to tell from the pictures, but is it possible you've got the input jack wired up wrong? It kind of looks like the tip connect is soldered to a black wire, and it looks like the black wire is running to V-/ ground? Sometimes the location/orientation of the solder points on those jacks can be a bit confusing, but you can usually tell by matching up the metal layers of the "sandwich" at the base of the jack.

Also, be sure you have the transistor in the proper orientation. I couldn't get to the schematic, so I'm not sure if yours is correct or not, but in such a small circuit that's a good first thing to check.

Oh, and make sure none of those leads are shorting ;)
Title: I think I've got it
Post by: ErikMiller on September 23, 2003, 02:54:31 AM
I believe you've got the transistor in backwards. That is, you have the collector and emitter reversed.
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: puretube on September 23, 2003, 03:00:37 AM
is your input (0.1uf cap) actually connecting to the tip of your guitar-cable? (can`t see it properly in the pics).




//www.puretube.com
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: Peter Snowberg on September 23, 2003, 03:14:24 AM
That looks great!  8)  :D

I think Erik got it. Turn the transistor 180 degrees.

One more thing to do.... melt a little solder along those traces to coat them. If you have any hairline breaks, that will solve them. It also prevents oxidation from killing the board down the road.

Put the pot back, flip the emitter and collector, and get ready for success! 8)

-Peter
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: Oliver on September 23, 2003, 06:45:59 AM
Quote from: Peter SnowbergThat looks great!  8)  :D

I think Erik got it. Turn the transistor 180 degrees.

One more thing to do.... melt a little solder along those traces to coat them. If you have any hairline breaks, that will solve them. It also prevents oxidation from killing the board down the road.

Put the pot back, flip the emitter and collector, and get ready for success! 8)

-Peter

Hi,

the Tranni looks good for me (the View from top looks all right for me).
But the Input Tip seems to be connected to the Black Wire (what cable is it - the Battery - ?)

Perhaps check that first and if you are 100% sure, that the Input Jack is connected right and there is no funktion anymore, turn the Transistor.

but i can be wrong - its hard to see on the Pictures..

bye
Oliver
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: Rory on September 23, 2003, 07:59:06 AM
The schematic has the tranny in correctly, but if you look at the wiring layout, it has the actual picture in wrong.  The EBC's are right, but the picture is incorrect.  I did the very same thing when first doing this project, but wrote down the corrections on the printed schem.
Title: Can someone look at this and tell me what I'm doing wrong?
Post by: puretube on September 23, 2003, 08:18:00 AM
see:
http://www.epanorama.net/links/components.html

or:
http://www.fairchildsemi.com/ds/2N/2N3904.pdf

and it looks the 2n3904 is inserted upside down