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I'm a little confused by the letters in the materials list next to the capacitor values.  When I go the sites to buy caps  I see uF and pF and mF but no n caps.  Do I need to convert the values? 

Yep.  Some sites like to use nF (nanofarads), others don't and will use thousands of pF (picofarads) for lower values and thousandths of uF (microfarads) for higher values.

1000pF = 1nF = .001uF

And what is the values for the ones listed as 2n2 or 1n8 and such.  I'm just starting to study this sort of thing and what I am seeing in the stores don't seem to match the stuff on the list.

When you see values like this, treat the unit indicator like a decimal point.  So 2n2 = 2.2nF (= 2200pF ).  You'll see that in resistor values, too, sometimes with k, as in 2k2 = 2.2K.  Sometimes you will see the unit indicator preceding the value, as in u22.  Again, just treat it like a decimal point.  So u22 = 0.22uF (= 220nF).

Edit to add: And just for the record, in this context u is just the Roman alphabet stand-in for when you need to represent the Greek letter μ (mu) for micro.

I agree with Rob.  Check across those two components.  The drop across D2 should be less than 450mV.  The drop across R12 should really only be about 50mV (assuming 2.5mA/op amp and no R13+LED).  If the drop across D2 is high, then, yeah, it's a bad diode.  If the drop across R12 is high, you've either got an incorrect (high) value in R12 or you have a short that is causing excessive current draw.

Congratulations, Rob!  When the Madbean wiki is created, you will have already written the entry for "Unused Op Amp".    Seriously, I'm filing this stuff away.

Took some readings with the multimeter

from pins 1-8:

3.34v
3.3v
3.315v
0v
5.93v
5.78v
5.73v
0v

that don't seem right ?

Ang3lus, looking at what Rob and Jon have added here, it occurs to me that your voltages make total sense (a.) if you're using a depleted battery, and (b.) if you counted the pins incorrectly.

You have voltage on pin 5 where you should have 0V (ground) and you have 0V on pin 8, where you should have your highest voltage (supply).  This is exactly what I would expect if you were counting pins from top to bottom on both sides.  You should count pins starting at the top left pin (1, just left of the notch) going down and continuing counter clockwise from there.  In other words, you count down the left and then up the right sides of the IC.

(Jon obviously figured this out, but didn't mention the pin counting error.  I was too stupid to catch that the first time around.)

22UJ100

but the package i got it in says 100n

I actually decided to look at your photos.  Duh.  It really says µ22J100, and, yes, the position of the µ is important -- it's like a decimal point.  That means it's 0.22µF, or, as you guessed, 220nF.  J = 5% tolerance, and the 100 means it's rated for up to 100V.

Rob, thanks for the op amp information!

Your voltages are correct -- for a battery that's only putting out 5.93v. Use a fresh battery or a power supply and take voltages again.

Jon brings up a good point.  If you were using a battery when you blew through R12, you may have significantly depleted the battery before the resistor fried...although I'm not sure if a 9V battery would provide more current than a 1/4W resistor could handle.

Jon, would he see any voltage on pins 5-7?  That op amp is grounded and unused.  (Sure, I could breadboard it, but I'll bet good money you've built this one.  )

Took some readings with the multimeter

from pins 1-8:

3.34v
3.3v
3.315v
0v
5.93v
5.78v
5.73v
0v

that don't seem right ?

checked R6 and R7 values, they seem  fine at 390k and 470k,

That is strange.  First off, I would expect to see somewhere between 8-9V on pin 8.  If that's really 0V, the op amp is not going to work.  Second, pins 1-3 look a little low.  I would expect to see something between 4-5V.  Third, I wouldn't expect to see any voltage on pins 5-7.  I recommend reflowing all the joints on those IC pins and double checking for shorts (to ground or elsewhere) with a multimeter. 

With the power disconnected, confirm pin 5 has continuity to ground.  Confirm pin 8 has continuity to the positive leg of C8.

c9 is a filtering capcitor ? tayda has a weird way of writing values on the capacitors, so either this is 100n or 220n, would it matter if the value is 220n?

It wouldn't matter enough to cause any problems.  What is written on it?

what could be wrong in my build?

Anything.  Seriously.

Go to the Tech Help section of the forum, read the sticky posts about how to post a request for help, and open up a thread there with the information that will allow someone to help you debug your pedal.  To start with, include a link to a schematic or build document, a description of the problem, voltages of all IC or transistor pins and good photos of both sides of your board.  If you have questions about how to do anything, just ask.  You'll get help.  But you've gotta give us something to work with first.  Good luck!

Thanks for the photos.  I realized I had been looking at the Moodring 2015 build doc, but you are working on the 2014 board and there are some slight differences.

The output appears to be coming off of the wrong lug of your Multiplex 3PDT.  Output from the board is coming into the corner lug as it should, but it looks like you have the wire that would normally go to the output jack (but in your case should go to the Input pad on the Moodring board) connected to that same lug.  It needs to go by itself on the lug below that.

I think everything looks okay on the Moodring's 3PDT, but let's see what happens after you fix the Multiplex's 3PDT.

Edit:  Yep -- jimilee beat me to it.

Voltages on all the IC and JFET pins wouldn't hurt, either.

Also, your R3 and R4 resistors look like they might be 47R instead of 470K.  Is that multiplier band orange or gold?

Oh, and R6, too, which if it is 47R would totally blow out your R12.

Nice demo.  I had written that OD off based on samples I'd heard a couple years ago, but yours sounds great.  And, yeah, I love the way it sounded when you rolled back your volume.

*Noise problems as in white noise from pt2399 chips?

Like I said, I don't really know what I'm talking about.  I read a couple of things recently, including this thread about heterodyning (which seems to implicate charge pumps and BBD clocks more than PT2399s) and a web page about running more than one digital circuit off the same power supply (which I can't find anymore).  I'll look for it again later tonight.

When I wired them up  the delay works but reverb does not. Reverb alone produces a high pitched wine.

If the Multiplex delay works while both effects are wired together, this suggests that you're connecting the Moodring board input and output pads correctly, and that the Moodring's buffer works, but you probably have a problem with the Moodring's 3PDT wiring.

You should be able to connect a true-bypass Multiplex and a buffered bypass Moodring without any switching problems*.  Just connect the output wire from the Multiplex's 3PDT directly to the Input pad of the Moodring board, then connect the Output pad of the Moodring board to the tip lug of your output jack, and wire up the rest of your Moodring board like the buffered bypass diagram in the build doc.

Have you tested the Moodring in buffered bypass mode separate from the dual-effect setup?

You may want to upload photos of your wiring if you still have problems.  Good luck!


* There could be noise problems sharing two digital effects on the same power supply, but I don't have any real experience dealing with that.

http://smallbear-electronics.mybigcommerce.com/alpha-single-gang-16mm-solder-terms-linear-audio-taper/

With the Boneyard you may need to jumper the high gain/low gain switch and the boost switch so that those circuits are complete.  I can't remember how those wer set up on the V1 board, though.  Let us know if you can't figure that part out.  In the meantime, I'll dig through my old build docs.

On the Crunch/High Gain switch (SW1) you will need to jumper the middle pad to the left pad for Crunch or the middle pad to the right pad for High Gain settings.  This would be very easy to test with a toggle switch or one pole of a 3PDT.

On the Boost switch, jumper the middle pad to the left pad to permanently disable the Boost function.