I just finished the Sprout build. The LED is working when I press the switch but the effect does not turn on.
Any advice on how to fix this would be appreciated. Here are some photos:
http://imgur.com/a/pgjde (http://imgur.com/a/pgjde)
I haven't made any substitutions for parts (I followed the BOM on the Sprout pdf), and I haven't made any troubleshooting steps. I'm very new to this so I am kind of lost on the whole situation.
Thank ya!
Hey man can we get a clear shot of the component side too? Also what transistors did you use?
These are the most common mistakes people make:
Incorrect Parts
Backwards Parts
Poor Soldering
Poor wiring.
You need to verify, then double check that all of those things are not your problem. Chances are one of them is. Go through your circuit and make sure your parts are correct, oriented properly, that you you have no cold solder joints or solder bridges and connections that shouldn't be made, and that your wiring is correct. From the looks of things, I would suspect one of those four issues, but the pictures don't really help me tell you which one.
An audio probe is the tool that can really help you at this point.
jacob
There are several spots on your board where it looks like you might have an accidental solder bridge to ground. Use a multimeter to test for continuity to ground at every spot on the board where you shouldn't expect that. Also, if you can post a backlit shot of the board, those can be amazingly helpful finding solder bridges on etched boards. Good luck!
I don't have any of the tools mentioned to check, so I guess I'll ask around to see if I know anyone that does because I'd rather not go out and buy one (still not sure how much I want to invest in this hobby as I am just starting out).
@Haber - For Q1 I used 2N3904 and for Q2 I used BC109B
I will post those photos of the backlit board and the component side shortly
Just a cursory look, I'm seeing a few possible solder bridges. Top left corner, the 3 big groups of solder points. Make sure there is continuity there, and there are no solder bridges. The top center solder point also looks to be a solder bridge. double check that one as well.
Could someone explain what a solder bridge is?
It's where a tiny strand of solder extends from where you intended to put your solder to some other place on your board where it isn't supposed to be touching. Thus it is "bridging" two places together. They are hard to see sometimes, but having even one in a bad place on your board can make the entire circuit not work. Testing for continuity can rule out or confirm there is a problem like that so that's a good place to start. Re-flowing your joints can also fix dead joints if you have any of those, so it's probably not a bad idea either.
And what is reflowing? haha :-\
Reflowing is applying a hot soldering iron to a solder joint to 'reflow' the solder on ye joint to make a better connection.
Jacob
Yes exactly. You're just re-melting every joint and then letting it re-solidify. Sometimes you don't get a good connection the first time and this can fix it up.
I tired desoldering (with a desoldering bulb) a few of the points where it looked like bridges were formed but I didn't have too much luck. It looks like they are still there. Can anyone look at this picture and tell me what I should do?
(solder side)
http://i.imgur.com/mbMPP.jpg (http://i.imgur.com/mbMPP.jpg)
(component side)
http://i.imgur.com/IGPxL.jpg (http://i.imgur.com/IGPxL.jpg)
(http://i.imgur.com/JTFcC.jpg)
http://i.imgur.com/JTFcC.jpg
In red are possible solder bridges that I saw. Make sure that there are no solder bridges at these points.
In yellow are solder points that I would hit again to make sure you have a good connection.
Do you have any desoldering braid? If not, you really do need to at least have that to fix mistakes.
EDIT: lol we both posted the same thing :)
Hi themachinerages,
You need to be very careful when soldering that you dont accidentally connect something thats not supposed to be connected (a solder bridge). I would recommend practicing your soldering on some vero board, just to get the basic feel for how to do it. You dont want to put too much solder on, and you dont want to put too little solder on either.
I have edited your photo to show you a couple of places that you might want to check for solder bridges. I have also included the corresponding PCB layout, so that you can see what i was looking for (there should be a gap, but there isnt). Some of them may not be solder bridges, its hard to tell from the photo but i have included them so you can check them anyway. I would suggest following that pcb layout around your board with an exacto knife / sharp knife and lightly scratching the gaps between the tracks, scratch away the flux (the translucent, browny / yellowy stuff) and check for solder bridges. Go around the hole board methodically.
I hope this helps you to get the board going. Stick with it mate, its worth it trust me ;)
Paul
Looks like Chromesphere and I saw similar things. Go back to the solder pads that we pointed out and double check them
So should I try the xacto knife method first or buy the soldering braid (not sure how this works, I'll look up a video tutorial)?
Will the knife be able to scrape away the solder? I would imagine it needs to be melted for it to budge at all
Hi themachinerages,
The xacto knife wont get through large solder blobs. Its probably something you should try after you fix the solder bridges (if it still doesnt work). Try the solder braide method first. i would get a solder sucker though, i find they do a better job. You can pick one up for about 8-10 dollars.
good luck,
Paul
I got one of the desoldering bulbs and it didn't help too much (one of these: http://rsk.imageg.net/graphics/product_images/pRS1C-2160655w345.jpg (http://rsk.imageg.net/graphics/product_images/pRS1C-2160655w345.jpg))
I guess I'll go buy some desoldering braid. I hope this works!!
I use the bulb quite a bit right now. I also use braid. You should be able to use both.
Jacob
Hi
I also noticed you're using solid core wire. You may want to check continuity from end to end on each of those as well to make sure you don't have a break in one.
HI themachinerages,
I use one of these, a solder sucker. Might be similar to the solder bulb? idk ive never used a solder bulb. I dont use braid either, I used to, but i found it didnt work very well at all (for me personally). The solder sucker does the job for me.
http://www.google.com.au/search?tbm=isch&hl=en&source=hp&biw=1016&bih=512&q=solder+sucker&gbv=2&oq=solder+sucker&aq=f&aqi=g1g-S9&aql=&gs_sm=e&gs_upl=187l3312l0l3406l24l12l1l0l0l0l391l1234l2-2.2l5l0
Good luck,
Paul
They essentially do the same thing. A solder bulb is a little bit more manual. I find the bulb easier to use than the big unit.
However, the desoldering iron madbean uses is where it's at!
Jacob
Still no luck!! I tried the braid and cleaned everything up with the xacto.
What tool do I need to check continuity? Maybe it's a faulty part
At this juncture I would use an audio probe. Start from input and work your way around the signal path to see where the signal breaks.
do you have a digital multimeter (dmm)? that is the tool you use to check continuity, among other things. you just about HAVE to have a dmm for diy electronics, even if you're building from a kit. almost as important as a soldering iron, imho.
I don't have a DMM and I'm not sure if I want to invest too much money as this is my first project and I don't know how long I will be involved in this hobby.
Would the audio probe option be a cheaper solution?
audio probe would be a cheaper solution, as you can make one yourself if you have the right materials, but a DMM can cost as little as 18 dollars on Amazon.
I saw that post that jkokura made about building a testing rig, but is there a simpler way to do it that wouldn't involve desoldering the board from the enclosure?
If you've got your board soldered to the enclosure then it probably isn't going to work. In most cases however, you should be either able to use a probe on the board without taking it out, or simply by removing the guts from the enclosure. That should be fairly easy to do.
At this point, both tools are going to be important to use in order to see what's really going on. A Multi Meter is important because it will be able to measure voltage on the board, and it will allow you to check continuity which can be helpful in finding solder bridges. An Audio probe can help you find where your audio is 'stopping', which can find cold solder joints and incorrect or backwards parts. An audio probe can be as simple as a 1/4" jack, a capacitor, and some wire. For a Multi Meter, if you don't want to buy one, try asking around and seeing if you can borrow one. Chances are high that one of your friends or family, or your friend's family will have one that you can use for a little while! They're very common tools.
The testing rig is only really worth building if you build pedals often enough or do debugging often enough to justify it. I used a spare enclosure and some extra parts so it really was quite cheap for me, but I can see how it might not be for other people.
Jacob
By desoldering the board from the enclosure I meant desoldering the wires attaching the board to the input/output/dc/etc.
I'll see if I can find someone I know with a multimeter.
What would the specs be for making the probe?
I think if you search you should be able to find them. Really, all you need is a jack. Connect the sleeve lug to a wire and then connect that to ground of the PCB/jacks/switch. Then put a 100nF cap on the tip lug, and a wire from the other side of that cap. That wire is now your probe. Plug the probe into your amp and keep the volume low, and plug your guitar into the input of the pcb. Then you can probe around on the board. Lots of popping and noise, but if you listen you should be able to hear the signal at where the input wire goes into the board. Follow the circuit along with a schematic and layout and you should be able to find where the signal should go and where it shouldn't.
Jacob
Stereo or Mono jack? Does it matter?
I think I could definitely do this if I go buy a jack from Radioshack
Does anyone know if I need a stereo or mono jack?
Either will work. Mono is probably easier.
Jacob
Thanks!
I built the probe and bought a multimeter. I have no idea how to use the meter and when I use the probe, I get no signal at any point on the board, even when I touch the probe to the input point.
I am getting really frustrated with this. Does anyone have some advice for me?
The best thing you can do with the DMM right now is check for continuity to ground from points in the circuit that should not have continuity to ground (i.e. shorts). Set your DMM to Continuity Test setting. Clip (or hold) your black lead to the ground plane of the board and then touch other portions of the board. Confirm that parts that should be directly grounded are and that parts that should be, aren't.
As for the signal probe, if you're not getting signal at the input of the board, then your wiring may be wrong or you may have cold joints on the switch. The only place I have ever had a cold joint (at least one that affected the signal) is on a 3PDT switch, so that's the first place I'd look. Start testing for signal at the input jack and follow it through the switch.
If you can't get signal at the jack, your signal probe may not work. Are you grounding it? Good luck!
I have the probe grounded, yeah.
I am almost sure that I have the wiring correct and I resoldered for cold joints.
So I should have no continuity to the ground wire from any point? and if I do have a spot grounded, how do I fix that? You mentioned some parts should be grounded, how do I know which?
I apologize if these are amateur questions, I'm a complete beginner
To determine which parts of your board should and shouldn't have continuity to ground, you need to figure out which parts of the board correspond to certain parts of the schematic. That may sound tough if you've never done it before, but it's a good exercise and a skill you'll need to pick up if you ever want to successfully debug a board. Maybe someone with more time can mark up an image for you.
In the meantime, although you feel like your wiring and switch soldering is good, you can't detect signal at the board input with your new probe. You really need to figure out what's going on here before you tackle the board.
Based on what you've said, there are several possibilities:
- incorrect wiring
- cold solder joints on the jack or switch
- bad hardware (jack or switch)
- non-functional signal probe
- incorrect use of signal probe
- guitar plugged into wrong jack (don't laugh, we've all done it)
I think the first thing you should do is confirm that your signal probe functions correctly. With your probe plugged into your amp and the guitar plugged into your input jack, connect the probe ground to the sleeve (ground) lug of the input jack. Strum the guitar and touch the signal probe tip to the tip lug of the input jack. Heck, touch it to the tip of the cable plug itself. If you get sound, the probe works; if you don't it doesn't.
If it works, start tracing the signal from the jack towards the board. Do you have signal on the input lug of the 3PDT switch? If not, you've got a cold joint or a broken wire on that connection. Moving on, do you have signal on the output log of the switch (the one that connects to the input of the board). If not, you've got a cold joint or a broken wire or a bad switch.
Good luck, and let us know how it goes.
Thanks for the responses mgwhit!
I tried your test to see if the probe is working and it appears that it isn't :(
I followed Jacob's specs so I'm not sure what I did wrong
Perhaps a picture of what you're working with might help us see what's going on for you?
Jacob