Egodriver Problem

[jkokura]

That's the connection between your parts and power. Since R3 connects to the parts connected to your 9V, it will likely now be that the problem rests in the parts connected to your power supply.

Two things. Try a different power supply - a battery is best. Also, take a look at the schematic and carefully looking at the parts connected to your power. There's some electrolytic caps, some resistors and a diode in there. Check them out.

One more think I thought of, maybe disconnect the LED if you've got it connected...

Jacob

[tenwatt]

LED removed and the problem persist.

I'm using a Vodoo Lab Pedal Power 2 that's working well with everything else.

So you're saying test anything connected to the power...is that the "VB"?  What do you mean by "carefully look at"?  Probe?  Multimeter?  Visually inspect solder?

[jkokura]

All of the above.

Yes, try another power supply, battery preferred.

If you look at the schematic, there is a series of parts between the 9V and VB pads. All those parts are what I'm talking about.

Have faith, it will work eventually.

Jacob

[tenwatt]

R12, when probed, makes no sound on either side.  It read 9.25V on both sides.

[jkokura]

That's the current limiting resistor for the LED. That's correct, so any other parts?

Jacob

[tenwatt]

R13 - stutters - 9.25V to 8.85V
D2 - stutters - 8.85V to ground
C9 - stutters - 8.85V to ground
C11 - stutters - 8.85V to ground
R14 - stutters - 8.85V on one side but goes crazy and gives no reading on the other - measures 9.91k across the resistor
R15 and C10 also stutter and give no reading on the meter.

I'll keep going but I'm hoping R14 is the problem.

[jkokura]

K, you should have about 9v on one side of R14, and half that in the other side.

You have located a part of the issue.

Jacob

[tenwatt]

K, you should have about 9v on one side of R14, and half that in the other side.

You have located a part of the issue.

Jacob

Crap...just part?  I'll replace R14 what should I do after that?

[jkokura]

Check all your voltages, and see if the problem goes away. I bet theres nothing wrong with the part, rather the somehow there is a solder bridge or other small problem like that. It's just that voltage indicates a problem. By the way, you shouldn't audio probe on you power rail, sorry for indicating you can. You should just use your DMM there.

Jacob

[tenwatt]

By the way, you shouldn't audio probe on you power rail, sorry for indicating you can. You should just use your DMM there.

Have I potintially caused more problems by doing so?

Rather than just jumping in and desoldering it I tried scraping around the pads with a pick to make sure there were no bridges.  I cleaned it really well on both sides and retested it and there was still no change.  I'm going to pick up a desoldering iron and another 10k from Radio Shack today and give it a shot.

[tenwatt]

I desoldered R14, cleaned the PCB really well, and installed a new resistor...no change.

What's next?

[jkokura]

K, so you should be getting about 9 volt on one side of R14, and you should be getting approximately 4.5 volts on the other side. The side towards the 9V in is the side that should have 9V. I can't tell you more than what I've already told you I don't think. You need to search for what is causing that to not be true (I think). I can't think of another reason why this would be occurring, and unless someone else can pipe up and give us any other ideas, you need to keep searching all the parts for a part that might be incorrect, or backwards, or faulty, or just plain not soldered correctly.

One thing I can think of is your IC socket. Is it possible that some things are connecting where they shouldn't there? Try taking your IC out, then seeing if there's continuity between any of the socket terminals. If the schematic says there should be, then that's ok, but if there's continuity where there shouldn't be then fix that.

Jacob

[tenwatt]

Out of curiosity I pulled the IC out of the socket and measure R14 and everything was fine.  Socket?

[tenwatt]

Well, I'm completely put out.  It's to far above my head to figure it out.  I was so excited to take on building pedals but I already feel exhausted.

Thanx for all your time and help.

[jkokura]

Out of curiosity I pulled the IC out of the socket and measure R14 and everything was fine.  Socket?

Did you measure R14's value or did you measure the voltage?

If the voltage is fine, that indicates to me that either there is something wrong with the socket, or it's a problem with the IC. If you've measured the value, you can't rely on your measurement if the part is still in the board. As long as the bands are correct, you don't need to worry about it much.

Sorry man, it's tough sometimes. I've had many things go wrong with my builds, and it can be very frustrating indeed. You might just need to take a break for a few days or even a week or so. If worst comes to worst, I'll get it working for you if you send me the board.

Jacob