Author Topic: Built it but not working fully.  (Read 6080 times)

Built it but not working fully.
« on: September 23, 2006, 07:01:34 PM »
Right, I've finished building it and have just tested it out: when the effect is off everything works fine but when it is engaged I get no sound. If I put my finger on the transistor's case then my guitar signal gets throught to the amp but very weakly and a whole bunch of radio signals are picked up. ( I know I probably shouldn't have touched it).  I used a 2n2222a and a 4k7 pot instead of 5k. I can probably post some pictures if you need. The soldering was pretty messy and badly done but I don't think anything that needed to be connected wasn't or that anything that shouldn't have been was. I used stripboard because I got my parts at Maplin and that was all they had. I tested this circuit while it was in the box but with the base off.

Re: Built it but not working fully.
« Reply #1 on: September 24, 2006, 09:25:36 AM »
I have a digital multimeter but don't know how to take readings. If someone will tell me how then I will post my results. Also I don't have access to a digital camera at the moment, sorry.

$uperpuma

Re: Built it but not working fully.
« Reply #2 on: September 24, 2006, 02:47:49 PM »
black probe on a ground source and the red probe at all points you need to read... then write them down..
Breadboards are as invaluable as underwear - and also need changed... -R.G.

Re: Built it but not working fully.
« Reply #3 on: September 24, 2006, 05:22:16 PM »
Does the effect need to have the guitar jack plugged in?

$uperpuma

Re: Built it but not working fully.
« Reply #4 on: September 24, 2006, 05:37:10 PM »
probably, if you followed many of the wiring diagrams provided by the illustrious types around here that provide that type of thing.  I'd have something plugged in there, just to be sure... then test everything
Breadboards are as invaluable as underwear - and also need changed... -R.G.

aron

Re: Built it but not working fully.
« Reply #5 on: September 25, 2006, 02:33:50 AM »
From the build pictorial:

Quote
If I connect the components together correctly, it will work. It doesn't matter if they are "in the air" or on cardboard, as long as they are connected together correctly (not shorting), the circuit will work.

Somehow there is a wiring problem OR the wrong value components might be in there. Yes, the guitar jack needs to be plugged in for the circuit to have a complete circuit (the input jack turns the circuit on and off).

Re: Built it but not working fully.
« Reply #6 on: September 25, 2006, 08:33:32 AM »
Ok, i made some very stupid mistakes: The stripboard that I was using had a line down the middle which meant that not all strips were connected. I forgot to connect these up, I have now done that. I tested the circuit and it seemed fine. I then put some cardboard above and below it to stop it shorting to the box and closed  the lid. Then it the effect was much less noticeable and infact I'm not sure if it was working. I couldn't hear a difference from when the pedal was engacged or disengaged. I am at college now but when I get home I'll investigate further. Thanks for the help.

Re: Built it but not working fully.
« Reply #7 on: September 25, 2006, 03:23:06 PM »
It still doesn't work, I've taken some voltage measurements though. If you look at this layout http://aronnelson.com/gallery/album18/GUS_NPN_BOOST which I followed then I'll list the voltages: The voltage on each strip from top to bottom were as follows: 20.2, 0, 9.4, 5.8, 4.6, 5.9, 4.6, 0, 0. The voltages on the swithc and pot were all 0 except for the lug f the pot connected to the 4.6 strip which was also 4.6.

aron

Re: Built it but not working fully.
« Reply #8 on: September 25, 2006, 05:52:46 PM »
Quote
The stripboard that I was using had a line down the middle which meant that not all strips were connected. I forgot to connect these up, I have now done that. I tested the circuit and it seemed fine. I then put some cardboard above and below it to stop it shorting to the box and closed  the lid. Then it the effect was much less noticeable

You probably have a short or something happening if it worked before putting it in the box.


Re: Built it but not working fully.
« Reply #9 on: September 27, 2006, 04:25:56 AM »
Hmm, OK, I found a loose connection on one of the jack sockets and resoldered that but I still have problems. The sound when the pedal is dengaged and disengaged are the same volume (although I think the tone is slightly changed). Any ideas?

aron

Re: Built it but not working fully.
« Reply #10 on: September 27, 2006, 12:39:04 PM »
check out this page:

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0

It's hard to tell what's happening since you basically made your own layout. Obviously something's wrong but where to start?

Re: Built it but not working fully.
« Reply #11 on: September 28, 2006, 03:30:03 PM »
I didn't make my own layout I used the stripboard one in the gallery, I would have used perfboard but I couldn't find any here in the uk. I'll gather the information and post it soon.

Re: Built it but not working fully.
« Reply #12 on: September 30, 2006, 12:24:26 PM »
When I measure the voltages (again) should I measure before and after each component?

aron

Re: Built it but not working fully.
« Reply #13 on: September 30, 2006, 02:29:18 PM »
Well, right on the legs (or pads) of the components.  Not on the edges of the stripboard etc... right on the legs of the transistor etc...