Ruby Debugging Problem

[rbrenne]

Hi everyone.

I posted this somewhere else by mistake, and I'm sure this has been asked hundreds of times but I'm not sure what else to do...

I'm having a major problem debugging my Ruby amp I made using the ROG diagram.  I've been looking at the other topics, but can't seem to find a solution.  With everything connected I get a loud vibrating buzz from the speaker with no guitar signal coming through at all.  I've tripled checked the connections, looked for solder bridges, swapped my 100 cap with a 470, disconnected my LED thinking I may be overloading it. Nothing has been getting rid of the buzz and the volume and gain pots seem to control it.

Any other things I can try? I can't figure out why there is no guitar sound coming through at all. This is my first DIY so I'm pretty new to electronics.

Not sure if these pics will help, but hopefully an expert could catch a mistake somewhere.


<img "https://lh4.googleusercontent.com/-gv4HXN0qtEg/Tiet60dd81I/AAAAAAAAAEw/tklVCSJc4U8/s640/IMG_20110721_001733.jpg" /img>

<img "https://lh5.googleusercontent.com/-AppltjaZoYE/TiezAnOLCCI/AAAAAAAAAFI/9kAAvgA2rUY/s512/IMG_20110721_001745.jpg" /img>

<img "https://lh4.googleusercontent.com/-wKpTADf82K0/TiezYf-zJaI/AAAAAAAAAFY/UuIkBUjFXV8/s640/IMG_20110721_001754.jpg" /img>

<img "https://lh4.googleusercontent.com/-mj9BTtzsnjA/Tiezs_DlrtI/AAAAAAAAAFo/j5AuSN88z1g/s640/IMG_20110721_001810.jpg" /img>

<img "https://lh3.googleusercontent.com/-odPo2xBCPPQ/Tiez9Rxq7zI/AAAAAAAAAF4/xvq2_H2_8SY/s640/IMG_20110721_001917.jpg" /img>

Thanks!

[petemoore]

  Hum? what is the power supply?
   'Only Hum's ? Sounds like the circuit isn't yet working, debugging: What to do when it doesn't work thread illustrates the necessary debugging 'content', without voltages and reference information, debugging is either a quick-big hit , or a miss that may hide any useful clues.

[rbrenne]

I'm using a 9 volt for the power. The hum is really loud, and I'm getting no guitar sound. The pots control the hum as well.

[PRR]

You have an un-connected ground somewhere.

[askwho69]

You have an un-connected ground somewhere.

+10000

[rbrenne]

I tried reworking it. Now I have no buzzing, but I can't get any output from the guitar.  All of my voltages seem to be correct when I checked with the multimeter, and when I turn the volume all the way up I can hear the light static of the speaker.

Does this still sound like a ground issue?

Thanks for the replies!

[rbrenne]

Did some more troubleshooting today and didn't get much change.  Does it sound like I have something incorrect with my input jack? Not sure why voltages would be correct and pots work speaker white noise, but no guitar signal at all.

[Govmnt_Lacky]

IC, transistor, polarized cap orientation?

Sounds like a problem I had with my ruby and discovered that I put the IC in backwards 

[PRR]

> why voltages would be correct and pots work speaker white noise, but no guitar signal at all.

Signal is not getting from guitar to chip. Either not-connected somewhere or shorted-out somewhere.

Imagine you are an electron, coming off the end of the guitar cord. Is there a plausible complete path to the chip? Is there an easier path to ground, such as solder-wisp?

It can also be seen as rain from the roof to a rain-barrel. If the downspout is clogged, or broken, rain won't run to the barrel.