The lights are on but no-ones home! (SHO)

Forum dedicated to helping people debug and troubleshoot non-functional pedals or builds. Please use an clear and informative title, indicating circuit and basic problem. Don't forget to mark the issue as fixed if this is the case.
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itsthedevil
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my favorite amplifier: Vox ac4
Completed builds: Big Muff IC78, SHO Clone and a couple of Ruby Amps.
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Post by itsthedevil »

Sorry to be a complete pain in the keester! I have tried searching and can't for the life of me work out what has happened on my SHO project! I have every thing wired up etc - I get a clear sound when the pedal is switched on but when I hit the switch the led comes on but only a loud buzz comes out and no guitar sound at all. Again, sorry for the stupid questions! :oops:

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timnormous
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Post by timnormous »

I also have this problem. Did you ever work out what was wrong?

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CHEEZOR
Diode Debunker
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Post by CHEEZOR »

People would be able to help you easier if you posted the schematic, layout, and pics of your PCB (both sides). Its almost impossible to diagnose a problem like this without looking at all these things. Welcome to the forum, btw! :)

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juanro
Cap Cooler
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Post by juanro »

Short answer "you did something wrong"
For a more detailed response, please post a more detailed question.
La única verdad es la realidad.

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timnormous
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Post by timnormous »

Sorry, I was just trying to find out from itsthedevil if he/she ever resolved their problem. I wasn't quite at the stage of requesting help...BUT now I am!!!(please!)

So the schematic I used is this one: http://analogguru.an.ohost.de/193/schem ... ex_SHO.gif

I couldn't actually find the vero layout I used. I put the circuit together about 2 years ago and never got round to putting it into operation! Anyway I attached a vero layout based on the actual circuit. And some photos. I've gone over the gaps between each copper row with a razor and I've reset all the solder joints. Pedal works in bypass but when engaged quickly fades into a buzz which neither the pot nor guitar signal alter. Can anyone help me?! Thanks very much in advance. Sorry if I've committed any forum faux pas.

For the vero layout.
C1=100n
C2= 10μ
D1+D2= 1N4148
R1=5K1
R2=10M
R3=100k
R4=10M
Attachments
top side
top side
input starts top right
input starts top right
SHO vero Layout.png

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itsthedevil
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Posts: 17
Joined: 07 May 2013, 21:50
my favorite amplifier: Vox ac4
Completed builds: Big Muff IC78, SHO Clone and a couple of Ruby Amps.
Has thanked: 8 times
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Post by itsthedevil »

Hi again, I am really sorry for the late reply! The layout I have tried is the one that the amazing Nocentelli sent me on this thread: https://www.freestompboxes.org/viewtopic ... 51&t=22395 (I have tried to post the layouts but to no avail!) Here are a few pics to give you an idea on whats going on. Any luck yet timnormous? Thanks again for the support!
IMG_20130802_182921.jpg
IMG_20130802_182730.jpg
IMG_20130802_182800.jpg
IMG_20130802_182847.jpg
IMG_20130802_182908.jpg
IMG_20130802_182921.jpg
Sorry about the pics, I can send some more if needed.

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fishfude
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Post by fishfude »

Hey,

Your soldering is pretty poor (but don't feel bad, I'm gonna make some suggestions of how to make it better and easier) and I can see at least one point where it looks like it has crossed over the traces

Some things I would suggest to make soldering much more efficient: First off only use leaded solder. It has a lower melting temp and flows much better. Second, use a pointed tip for your soldering iron. You can get replacement tips for very little (google around). Use helping hands to keep everything steady (these guys: http://www.laventure.net/tourist/cables38.jpg). It makes a huge difference. Finally you have to make sure the surface you are soldering onto is hot enough to take the solder and let it flow evenly over its surface. To ensure this is the case, follow this procedure:

- Bring soldering iron down to veroboard surface, touching the tip where the wire/leg is coming through. The iron should be at about a 45 degree angle with the veroboard surface.
- FROM THIS POINT ON THE IRON WILL NOT MOVE!
- After 2 - 3 seconds bring solder down to the tip of the iron. Again at about 45 degrees to the veroboard surface
- DO NOT MOVE THE IRON ;)
- Use enough solder to comfortably fill in the veroboard hole and surround the wire/leg coming through (it must completely surround the wire/leg - just one side is not good enough - you can be a little more generous with the solder than your instincts are probably telling you).
- Remove solder
- Wait 2 - 3 seconds
- Finally remove iron.

Do this ^^^ and you'll be creating perfect solders every time. I hope that makes sense!

ff

I hope that helps

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