Snarkdoodle problem...

[mgwhit]

I should have realized that the ~3V drop is normal across the 1K resistor, so your 6.67V on pin 1 is normal.  Sorry if I made extra work for you there.

[mgwhit]

I meant to pick up my pedal at band practice tonight, but totally spaced on it.  We're playing out Saturday night, so I'll bring it home then and take a look at the voltages.  My concern is the voltage difference on your two inverter stages.  On your first inverter (pins 2 & 3) you have approximately the same voltage (~2.9V), which is a little less than half of your supply voltage.  This is similar to what we would expect to see in a normal three-pin op amp stage, except we would supply the bias voltage ourselves through a voltage divider.  I don't know if that's correct behavior for a hex inverter IC, but I suspect it is.  On your second inverter (pins 4 & 5) you've got the supply voltage on your input pin (5) and 0V on your output pin (4).  No continuity to ground suggests that there isn't a short there, but the fact that you have four chips that all show 0V on that pin suggests that it is not a bad IC.  This is baffling.  If you can wait until I (or someone else) can post voltages we may have a little more to work with.  In the meantime, I'd go easy with swapping out parts -- those etched boards can only take so much.

[dorrisant]

It was a set of four bad chips... I got new ones from a local store. Popped the first one in and saw big pretty signal at the output jack.

I had to plug it in and try it out... I will open it later and post the voltages.

Thanks to all for taking a look and helping... MUCH APPRECIATED!!!

Tony

[mgwhit]

If you've got another 4049UBE laying around, feel free to try it, but on an etched board a bad component is the last thing I would suspect.

Well, I eat my words.  Congratulations!

[dorrisant]

If you've got another 4049UBE laying around, feel free to try it, but on an etched board a bad component is the last thing I would suspect.

Well, I eat my words.  Congratulations!

No worries... You were doing what you could to help and I appreciate that.

Besides, when have you ever seen four chips in a row fail?

Tony

[selfdestroyer]

Nice man.. glad you got it going. Its a rocking pedal for sure. I recently built one for my aunt and she loves it.

Cody

[dorrisant]

Nice man.. glad you got it going. Its a rocking pedal for sure. I recently built one for my aunt and she loves it.

Cody

I only got to play it for about five minutes... I have to get back to the bench (translated=money). Sounded REALLY good! Can't wait to get some free time with it.

Thanks again for the encouragement and knowledge!!

Tony

[dorrisant]

Ok... Voltages as promised:
1- 5.78
2- 2.77
3- 2.78
4- 2.78
5- 2.78
6- 5.78
7- 0
8- 0
9- 0
10- 5.78
11- 0
12- 5.78
13- 0
14- 0
15- 5.78
16- 0

[selfdestroyer]

Very nice etch. Looks great and respect for you going the 1590A route.

Cody

[mgwhit]

Thanks for posting your voltages!  I finally got mine back, popped off the back and took a reading.  Pretty much the same: slightly less than 6V on the positive voltage power pin and slightly less than half of that on the active inverter input and output pins.  I definitely learned something from this.  Hope you're enjoying yours!

[dorrisant]

Thanks again guys!

I really hate it when posters have an issue , get great advice and then never post what the answer to the problem was. That is a waste of cyberspace. I have been guilty of it from time to time. If anyone is searching for those voltages they can find them quick enough now. So now we can have closure. 

Tony