Basically, Ive had trouble building my first pedal. It's a very simple fuzz.
Here is what happens:
First off, I plugged the DC jack in and bypassed the pedal, and got the amps clean sound. When it came to pressing the switch, nothing came through at all. But when I turned one of the pots it was sweeping a scratchy sound. I figured I would try to sort it out and unplugged the 9v jack. After doing this, I still got the amp sound because i was still plugged in. I then pressed the switch and got a rolled back version of what I got when the switch was bypassed.
I don't know what to do now because this should of been a very simple build.
Unfortunately the information you`ve given isn`t extremely helpful to someone trying to diagnose the problem. My guess though is you`ve wired it up wrong. Check the wiring methodically. When you`re satisfied you did everything right the first time, check it again. Then once more. Then again. Repeat.
This may sound a bit smartass but I can`t remember the amount of times I thought I`d done everything correctly only to find somewhere down the line that two crucial wires had been transposed.
If all fails there is a sticky thread entitled DEBUGGING-what to do when it doesn`t work (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0) which you should read.
Ive changed a few things but nothing really changed at all. I know it's too vague to point at specifics, but what is it most likely to be? LIke certain components?
Quote from: GREEN FUZ on July 27, 2007, 11:29:56 AM
Unfortunately the information you`ve given isn`t extremely helpful to someone trying to diagnose the problem. My guess though is you`ve wired it up wrong. Check the wiring methodically. When you`re satisfied you did everything right the first time, check it again. Then once more. Then again. Repeat.
This may sound a bit smartass but I can`t remember the amount of times I thought I`d done everything correctly only to find somewhere down the line that two crucial wires had been transposed.
If all fails there is a sticky thread entitled DEBUGGING-what to do when it doesn`t work (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0) which you should read.
That's exactly what I recommended to railhead yesterday
"...Always double check (or check as many times as needed), because our eyes can play tricks on us..." :icon_rolleyes: :o ::) :o ::) :o
CG ;D
I understand that, but is there a particular component associated for when things happen like this?
What is the circuit you`re working on? If it uses transistors it/they may have been put in the wrong way round.
It's an EZ face. It uses two transistors which I have socketed. SO turning the transistors was the first thing I tried.
You need to check out the Debugging thread, and post that information. Voltages of the transistors and so on will help others to find the problem. It's pretty likely to be switch wiring, but could be something else.
1.Read my original post to see what doesn't work
2.Name of the circuit = EZ Face
3.Source of the circuit (URL of schematic or project) = http://img502.imageshack.us/img502/9483/ezfaceezri8.jpg
4.Any modifications to the circuit? Yes, I added a 9v dc socket.
5.Any parts substitutions? Yes, I used a AC187 instead of 2SB33
6.Positive ground to negative ground conversion? I was told that it is a positive ground.
Quote from: dannyg on July 28, 2007, 02:37:01 PM
5.Any parts substitutions? Yes, I used a AC187 instead of 2SB33
6.Positive ground to negative ground conversion? I was told that it is a positive ground.
This might be your problem. The circuit is positive ground. The 2sb33 is, as far as I know, a PNP transistor. You have replaced it with an NPN trannie. Get yourself another PNP, anything will do for now. If you have another 2N3906, stick it in. Observe the pinouts closely. On the schematic the letters C, B and E relate to the COLLECTOR, BASE and EMITTER respectively. It is important that the correct leg fits in its corresponding hole. Pinouts vary from one trannie to another so if you don`t know what yours are you`ll need to find out.
I have used the transistor that the schemeatic information said I could use as a sub. Strange?
Quote from: dannyg on July 28, 2007, 03:55:08 PM
I have used the transistor that the schemeatic information said I could use as a sub. Strange?
Sure is, what can I say? This is the Joe Gagan easy face from GGG, right? The site is down at the moment so I can`t access it. Are you sure it didn`t say ac188?
It`s supposed to be a great sounding circuit so stick with it.
It is the Joe Gragan one yes, but it's the EZ diagram i'm using haha. But then somebody was kind enough to draw me up a layout. Im pretty sure it is the ac189.
Luckily I have a printed copy, i'll scan it in.
(http://img502.imageshack.us/img502/4374/joegaganof8.jpg)
That`s a big ol` schematic ya got there. ;D
Nevertheless, it just confirms for me that it is indeed positive ground. All the substitutes recommended are PNP.If you`ve used an ac187 it wont work.
Quote from: GREEN FUZ on July 28, 2007, 04:47:32 PM
That`s a big ol` schematic ya got there. ;D
Nevertheless, it just confirms for me that it is indeed positive ground. All the substitutes recommended are PNP.If you`ve used an ac187 it wont work.
Haha!
I'm using a ac128 not 127..
Ok. The ac128 is fine. This still leaves quite a lot of probable/possible causes of your circuit`s failure. So, you`ve read the debugging thread. Have you got a multimeter? If you do and can provide the figures as instructed in the aforementioned thread you will find a lot of people on the forum will be very quick to help as the voltage readings give a lot of information. If that`s not possible the next best thing is to upload some photos, as clear as possible, both sides of the board.
I cant get any clear photos, but I tried to scan it for fun before and it was crystal clear. I will try and scan them in tommorow. I'm going to see if I can get hold of a multimeter.
EDIT: can't seem to get the best of scans but here they are.
I had to disconnect the wire from the trimpot to the ground because it wasn't long enough to let the board fit the scanner. I know I should If taken all the wires off lol but I didn't.
Also, I can't get a good picture of the component side because the scanner blurs if it's too far away and the transistor are quite high up.
Ill post the layout aswell just incase it helps.
(http://img410.imageshack.us/img410/3113/boardside1zw5.jpg)
(http://img402.imageshack.us/img402/1966/ezfaceperfcy4.jpg)
Ive added the picture and layout.
Well it looks to me like you need to cut the copper tracks so not everything gets shorted... ;)
The drawing you followed has connective points and you've used a stripboard, judging from the picture you haven't
cut any of the tracks...
Your problem is basically that you didn't make any cut to the traces and all are shorted. And you have to redo the layout, because some parts are aligned with the traces and they are doing nothing in the circuit (ex. one of the transistors) or try to cut the traces.
CG
Right. Where to start.
First off I have a minor doubt about the layout you`re using. I`m not sure C2 and R4 are correctly placed. That said I`m not all that familiar with Veroboard as I never use it.
Which brings me to my next point. As I said the layout you`re working from is Veroboard. As far as I can tell from the scan you`ve provided, you are working on stripboard. With veroboard one needs to provide all the traces between components either by soldering the legs of components together or by means of lengths of wire to form the circuit. With stripboard some of those connections are already provided in the form of electrically conductive strips of copper which form the board but you will have to make cuts where no connection is needed.
Personally I hate stripboard having had a couple of unsuccessful attempts using it. I find the gaps between the strips too inviting for stray blobs of solder to create unwanted bridges.
Which brings me to my next point. Soldering technique. Yours looks not unlike my first few attempts. Suffice to say it`s something that needs practice. Just to make the point, this is my first effort.
(http://i117.photobucket.com/albums/o44/RANCHERO23/strip.jpg)
It never worked. Unless you count the loud humming noise it made when plugged in. (If I could get it to hum in tune I might be onto something. The Hum-Master ?)
I would be tempted to start again with a good stripboard layout. Let me know and I`ll point you in the right direction.
(couple of posts were made while I was writing this so apologies if this sounds repetitive)
Quote from: GREEN FUZ on July 29, 2007, 09:01:35 AM
(couple of posts were made while I was writing this so apologies if this sounds repetitive)
Anyone with an album like this... needs never apologize in anyway what-so-ever
http://aronnelson.com/gallery/album174
cold solder NO.1?
(http://i194.photobucket.com/albums/z305/owallgren/green.jpg)
oskar
So let me get this correct. I need to cut the connection of the copper board so that the copper doesn't connect components in that strip? Can I just use a knife to make cuts down the copper?
Whatever does the job... since you've made all the connections in other ways you just cut all the traces in between solder-joints.
Quote from: dannyg on July 29, 2007, 09:39:11 AM
So let me get this correct. I need to cut the connection of the copper board so that the copper doesn't connect components in that strip? Can I just use a knife to make cuts down the copper?
Yes, but only the ones that are shorting the circuit. And yes you can use a knife, but carefully ( cut only the traces not your fingers). :icon_lol:
CG ;D
I dont want to start cutting the wrong things so I need to clarify something. I understand what you mean and the reason behind it. But for some reason I can't seem to spot which ones they are. Could you please point them out so I dont cut the wrong thing?
QuoteAnyone with an album like this... needs never apologize in anyway what-so-ever
http://aronnelson.com/gallery/album174
You`re too kind.
Quotecold solder NO.1?
:icon_biggrin: The first of many.
Quote from: dannyg on July 29, 2007, 09:39:11 AM
So let me get this correct. I need to cut the connection of the copper board so that the copper doesn't connect components in that strip? Can I just use a knife to make cuts down the copper?
Yes you can use a knife if needs be. I`ve used a drill. You can also use a proprietary tool the name of which escapes me presently. Basically any means to sever those connections. Particularly where, for example you might have a capacitor or resistor lying across the length of the strip.
Look this shows it better than I can explain it.
(http://i117.photobucket.com/albums/o44/RANCHERO23/easyface.gif)
I would recommend you to use this layout as it particularly applies to stripboard. It even indicates exactly where to cut.
p.s If anyone wants this removed for copyright infringement I am only too Happy to do so. (i`m such a slow typist. Three more posts while I was pecking this out)
The problem is you made a layout for perfboard and used a veroboard. Check the GREEN FUZ's layout and see what I'm saying.
CG
Quote from: dannyg on July 29, 2007, 09:57:16 AM
I dont want to start cutting the wrong things so I need to clarify something. I understand what you mean and the reason behind it. But for some reason I can't seem to spot which ones they are. Could you please point them out so I dont cut the wrong thing?
It depends... If you have treated it completely like a a veroboard (the ones with little islands), then you have not used the
traces as conductor at all, right? Then cut between ALL solder joints... just cut, cut, cut, cut... :)
If you've used the strips as conductors, part in the construction then I can't advise you... too much thinking. Thinking bad. Cutting good.
The easiest thing would be to start all over with a veroboard. The next easiest (in my opinion) would be to cut between ALL joints and
then use shielded wire from the component side to fix it if you cut one trace to many...
EDIT! Two posts up... REDO with this layout... you'll be rocking tonight!
I think I will redo with taht layout thank you. Need a little advice though. The board I have is only conductive on one side. Do the components go on this side and I solder on the same side aswell? Or does it go underneath? Also, on that layout, how do I tell which is each pin on the transistors?
Quote from: dannyg on July 29, 2007, 10:46:25 AM
I think I will redo with that layout thank you. Need a little advice though. The board I have is only conductive on one side. Do the components go on this side and I solder on the same side aswell? Or does it go underneath? Also, on that layout, how do I tell which is each pin on the transistors?
No, the components go on the "components side" (the one without copper traces). For the transistors pins, check their respective data sheets.
CG
I need a little of advice because I don't think my resistors will fit just two tracks.
Don`t worry, they will. It doesn`t all have to be laid out flat. To make a nice compact layout designers often have components sticking up. As long as the two legs connect where they are meant too you can bend them any way you like..
Some words of advice.
Print out the layout. If you follow it exactly you will succeed. Don`t forget it is viewed as though looking at the non conductive side. Note there is a bridge to be made which is the blue line directly below R1. If you have a spare resistor you can cut one of the legs off, bend into shape and solder into place. Otherwise just use a small section of wire. Don`t forget to cut the traces where indicated (red dot within red square). There`s one under R3 aswell. Careful with that knife ;).
Take your time.
Careful with the soldering. Only use as much solder as is needed to make a connection. Don`t get any in the gaps between the traces (copper strips). Don`t apply the heat for too long as some components are sensitive to it. Particularly transistors.
As I`m in a good mood I`ll even help you with them.
(http://i117.photobucket.com/albums/o44/RANCHERO23/case-10.gif)
2N3906 viewed from below obviously.
ac128`s come in different packages. I don`t know what yours looks like so you`ll have to go here.http://forum.musikding.de/gallery/displayimage.php?pos=-1082 (http://forum.musikding.de/gallery/displayimage.php?pos=-1082)
There may be a red dot or a small tab which usually indicate collector and emitter respectively.
And finally, if there was any doubt I`ve marked on Andrew`s layout where the pins should go.
(http://i117.photobucket.com/albums/o44/RANCHERO23/easyface.jpg)
Try following the original schematic while consulting the layout, it`s a good way to learn. Good luck
wow, thank you very much. You guys have been very helpful.
About the resistors, alot of them have already been cut short. Can I just solder some lead back on?
I also find this site useful for transistor pins
http://modecideas.com/faq91.html
Yes, if you need to you can solder a surplus bit of wire on to extend the leg.
One last word. C1 and C2 are electrolytic capacitors meaning they are polarized and need to be correctly oriented. The little bit of grey shading on the layout shows the negative side. There is usually a marking on one side of your cap to indicate negative. Make sure it matches the layout. Keep us posted.
^ I already knew that but thank you :D
Ok, ive done the board, I just need help connecting it up to the external wires. You see, i'm not sure what all the different things on the side of the layout mean.
Most of it is pretty self-explanatory.
-9v will be, in this case, the black lead from your battery clip. Just solder it to the hole in the corresponding trace.
The rest all relates to the pots, potentiometers, controls, whatever you want to call them.
Viewed with the shaft facing away from you and the lugs pointing downwards, they are, in order., 3, 2 and 1.
Again solder the lugs to their respective holes as indicated on the layout.
What sort of jacks have you got? Open or closed? Is the input jack stereo?
In any case you will need to solder a lead from the middle ( otherwise known as the wiper) lug of the volume to one of the lugs on your output jack. The other jack lug is connected, in the same manner, to ground which in this case is the bottom trace marked g. Find a spare hole and solder it in.
Im just concerned because it's totally different to the original way I had it wired. By this I mean things such as, I have pregain 3 connected to the footswitch. Does that mean I need another wire ?
Don`t be concerned. There`s more than one way to skin a cat.
Apparently.
There`s still a couple more connections to be made after that. You`re using a DPDT switch, right?
Quote from: dannyg on July 29, 2007, 01:13:41 PM
Im just concerned because it's totally different to the original way I had it wired. By this I mean things such as, I have pregain 3 connected to the footswitch. Does that mean I need another wire ?
pregain 3 doesn't go to the footswitch. You need a wire going from hole b1 to the footswitch, that's the input wire.
Also make sure you cut the trace under R3 it's a bit hard to see on the layout.
Yes, a DPDT. Problem is, it makes things more complicated.
I would leave out the footswitch for now, just wire the input and output from the board straight to the jacks. That way you can test that the circuit is working, once you know it works deal with the footswitch.
Quote from: slacker on July 29, 2007, 01:23:54 PM
I would leave out the footswitch for now, just wire the input and output from the board straight to the jacks. That way you can test that the circuit is working, once you know it works deal with the footswitch.
Good advice. Let`s get this thing up and running.
The switch shouldn`t make things too much more complicated. Have a look at the original schematic to see how it should be wired.
Put any thoughts of the first layout, out of your mind, as though it never existed. They will just confuse you.
Ok then, so how do I wire it so there isnt a switch?
Think things will be on a hold for a while until I get another cap, the leads on it are way too small.
Along with the cap needing a replacement, some of the copper in a small area as come up. I'm guessing I can still use it? It's a part before some cuts so it's quite issolated anyway.
Also, one of my resistors is slightly darker on one end. Could this be a sign of it being burnt out? Thanks.
Quote from: dannyg on July 29, 2007, 06:06:06 PM
Along with the cap needing a replacement, some of the copper in a small area as come up. I'm guessing I can still use it? It's a part before some cuts so it's quite issolated anyway.
Also, one of my resistors is slightly darker on one end. Could this be a sign of it being burnt out? Thanks.
No, don't worry! We'll take care of it if it doesn't work when you try it... :P