Help getting my Yellow Shark louder.

[davidnlsw]

I made a thread about this a couple days ago in "General Questions." I put together a Haberdasher Yellow Shark PCB.

The effect sounds great, but I'm not getting unity volume even with the volume pot dimed. I can't figure out why. Here's what I've done to try to resolve the problem:

Rewired and resoldered everything off-board. Double and triple checked component values, placement, and orientation.

I took some DC measurements:

IC
1= 0.09   5= 0.09
2= 4.51   6= 4.51
3= 3.25   7= 9.02
4= 0.00   8= 4.78

Q1 (2N5457)

G= 0.00
S= 0.18
D= 8.51

Here's a few pictures. I don't know how helpful they'll be because they're pretty blurry, but it's the best I can do with what I have right now.

http://i.imgur.com/muv20WI.jpg
http://i.imgur.com/ZIRgM5H.jpg
http://i.imgur.com/MSZLLsK.jpg
http://i.imgur.com/1LVyiwd.jpg

So the only question I have for you all, that I could see as a problem is this:

When I tested all the resistors before I populated the PCB, they all checked out fine except for the 1M resistors that are R1 and R10. Of the 10 1M resistors that Tayda sent me the highest any of them would read with my multimeter was around 600k. Since everything else was fine I figured I'd just wire it up anyway and fix it later if it was a problem.

I had to do another order from Tayda the next week so I went ahead and ordered another strip of 1M resistors. Those all measure around 500 to 600k as well. Am I measuring them wrong, or are these all defective resistors that I need to replace?

The other problem, since I redid all my wiring the LED indicator is staying on all the time regardless of whether the effect is on or off. I've checked to make sure nothing is touching that isn't supposed to, it's wired exactly like it was the first time as far as I can tell, yet it is always on now. I even reversed the LED to make sure I didn't have the + and - backwards and that wasn't it.

Thank you all for any feedback and help you can give me. I'll try to answer any questions as best I can.

I'm really hoping the problem isn't some defective capacitor that I'll have to dig around for..


-David

[Haberdasher]

i can't tell anything from the pics; too small & too blurry I'm afraid.  but the voltages look about right to me.  possibly a tad high on pin 3 & the drain compared with mine, but that may not be a big deal, I dunno.

1M carbon film resistor bands usually go brown, black, green & gold.  do your r1 and r10 look like that?

[davidnlsw]

1M carbon film resistor bands usually go brown, black, green & gold.  do your r1 and r10 look like that?

Yeah, they are brown-black-green-gold.

That's the first thing I checked. I thought Tayda might have shipped me the wrong resistors, but that was not the case.

I just have a hard time believing that two separate packs of 10 from them would all be faulty.

Any ideas on the LED, guys?

I'm going to get a hold of a better camera tomorrow and take some higher resolution pics.

[das234]

Have you tried turning it up to ELEVEN? 


Sorry.  Couldn't resist the opportunity for a Spinal Tap reference.

[jimilee]

Check al your solder joints with a magnifyer. Reflow what you need to. I'l bet that will fix the issue. Got any better clearer bigger pictures?

[davidnlsw]

Check al your solder joints with a magnifyer. Reflow what you need to. I'l bet that will fix the issue. Got any better clearer bigger pictures?

Sorry, I'm a noob.

What exactly should I look for? How will I know what I need to reflow and what I don't?

Also… even more noob… solder joints are just the places I've soldered, right? There are some messy spots on the PCB. I'm still pretty amateur with an iron. Working on it.. but there are some spots I'm not proud of. If there are places where there is more solder than necessary, could that add resistance and decrease the output volume?

Better, clearer pictures should come tomorrow.  I don't have a camera other than on my phone. Going to borrow a better camera tomorrow to upload some pictures.

[davidnlsw]

Have you tried turning it up to ELEVEN? 


Sorry.  Couldn't resist the opportunity for a Spinal Tap reference.

Never apologize for a Spinal Tap reference. Never. haha

[jimilee]

Check al your solder joints with a magnifyer. Reflow what you need to. I'l bet that will fix the issue. Got any better clearer bigger pictures?

Sorry, I'm a noob.

What exactly should I look for? How will I know what I need to reflow and what I don't?

Also... even more noob... solder joints are just the places I've soldered, right? There are some messy spots on the PCB. I'm still pretty amateur with an iron. Working on it.. but there are some spots I'm not proud of. If there are places where there is more solder than necessary, could that add resistance and decrease the output volume?

Better, clearer pictures should come tomorrow.  I don't have a camera other than on my phone. Going to borrow a better camera tomorrow to upload some pictures.

It's how we learn, so ask as many questions as you need to. Solder joints are places where you've soldered. Make sure where the solder is touching other solder joints that they are supposed to touch. If they aren't it will add resistance or short out to ground all together. You can get some desoldering braid or a desoldering iron the clean some of that up. Just take your time and be patient. 

[davidnlsw]

Make sure where the solder is touching other solder joints that they are supposed to touch. If they aren't it will add resistance or short out to ground all together. You can get some desoldering braid or a desoldering iron the clean some of that up. Just take your time and be patient. 

Okay. I did make sure that all the solder joints are not touching any other connections that aren't already made by the copper. 

The thing that's confusing me is that the pedal sounds good, it's just too quite. No noise, no fizzy distortion or anything, it's just not as loud as it's supposed to be.

I borrowed a camera today. Here's some pictures that I hope are a little more helpful. If these are still not very useful I'll borrow a friends super high MP camera sometime this week and try to get some really HD ones.

http://i.imgur.com/ehV31Wl.jpg
http://i.imgur.com/0lGa3Xa.jpg
http://i.imgur.com/RY4weIr.jpg
http://i.imgur.com/MicxPLF.jpg
http://i.imgur.com/RqPE85u.jpg
http://i.imgur.com/93PvxRB.jpg
http://i.imgur.com/9zSgLmR.jpg

[jimilee]

Oh, is your led still lit all the time? I just went back and reread the op. Your led is grounding out somewhere, that would cause a volume drop in my experience. Check the wire that goes to your led. Does it do it in and out of the enclosure?

[davidnlsw]

Oh, is your led still lit all the time? I just went back and reread the op. Your led is grounding out somewhere, that would cause a volume drop in my experience. Check the wire that goes to your led. Does it do it in and out of the enclosure?

Yes, the led is still on no matter what. 

Before I boxed the effect it was not on all the time. Then I boxed it up and it was still functioning properly. Then I noticed that the output of the effect was low so I took the circuit out of the box and redid all of the wiring. Since then it's been on all the time. I can't figure out why. I've gone over the LED wiring a dozen times.

[davidnlsw]

*UPDATE*

I just wanted to give a quick update.

I put some more work into this build over the last week or two. I ended up melting my 3pdt while trying to redo some wiring. That got me thinking... maybe I had just been too hard on my 3pdt switch by taking forever to solder stuff and by applying heat multiple times (each time I rewired). I thought maybe that had been the cause of the weak output volume.

Anyways, I swapped out the 3pdt and used a different offboard wiring method than the Madbean diagram. I also wired my LED offboard instead of using the spaces on the PCB. This both solved the "light is always on" problem and solved the volume drop problem.

I just wanted to let y'all know that I finally triumphed over this lil guy and to say thanks to everyone who offered some help. Also thanks to haberdasher for the great PCB.