# No signal from Wonder Drive build



## Jared (Aug 23, 2020)

I’m working on a Wonder Drive pedal. I got it all built out and I’m not getting signal through the pedal when the switch is on.
I’ve checked for solder bridges, and made sure all polarity in the separate components are correct.
I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through; it’s after the first transistor in the signal. I’ve switched out transistor and the same thing is happening. No signal is coming out of pin 1 and progressing to the next resistor. 
I’ve attached a picture to help visualize. (Green is good to go, red is where the signal stops)
Any help would be greatly appreciated!
Thanks!


----------



## dlazzarini (Aug 23, 2020)

Jared said:


> I’m working on a Wonder Drive pedal. I got it all built out and I’m not getting signal through the pedal when the switch is on.
> I’ve checked for solder bridges, and made sure all polarity in the separate components are correct.
> I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through; it’s after the first transistor in the signal. I’ve switched out transistor and the same thing is happening. No signal is coming out of pin 1 and progressing to the next resistor.
> I’ve attached a picture to help visualize. (Green is good to go, red is where the signal stops)
> ...


What IC are you using?  If it’s the opa where did you acquire it?


----------



## Jared (Aug 23, 2020)

dlazzarini said:


> What IC are you using?  If it’s the opa where did you acquire it?


I am using an IC and it is an OPA from Smallbear electronics.


----------



## Jared (Aug 24, 2020)

dlazzarini said:


> What IC are you using?  If it’s the opa where did you acquire it?


OPA264AP


----------



## dlazzarini (Aug 24, 2020)

Jared said:


> OPA264AP


Ok just checking. Wanted to be sure it wasn’t some fake from eBay so we can eliminate that. I’m no pro at sorting through schematics but I’ll give it a go when I get a minute.


----------



## dlazzarini (Aug 24, 2020)

Jared said:


> OPA264AP


Just for shits and giggles do you have another dual opamp you could try out like a tl072 or a Lm4558 etc? I’ll say up front my troubleshooting skills are pretty limited as I’ve been extremely fortunate/lucky or both with all but my second build which turned out to be a cheap socket but I’ll try and look at the schem later


----------



## Nostradoomus (Aug 24, 2020)

Post some pictures


----------



## Jared (Aug 24, 2020)

Here are some images


----------



## Jared (Aug 24, 2020)

Nostradoomus said:


> Post some pictures


Thank you so much for your reply. 
I've posted some pictures below for reference!


----------



## Jared (Aug 24, 2020)

dlazzarini said:


> Just for shits and giggles do you have another dual opamp you could try out like a tl072 or a Lm4558 etc? I’ll say up front my troubleshooting skills are pretty limited as I’ve been extremely fortunate/lucky or both with all but my second build which turned out to be a cheap socket but I’ll try and look at the schem later


Sadly, I don't have an extra opamp available to try, though I'm not opposed to purchasing one if I need to. Thanks a lot for taking a look at that.


----------



## zgrav (Aug 24, 2020)

Can you explain what you mean here:  "I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through "

Is your test a digital multimeter?  Or are you using an audio probe?  A DMM is good for testing your connections between parts on a PCB, but won't let you test "through" a part unless it is a resistor (and then it would measure the value of your resistor, assuming no other parts connected those two points).

Have you tried an audio probe?  Easy to assemble from things you probably already have, and it will let you find out where your audio signal is being stopped.  You can search on google for building an audio probe, and find a number of posts in the forums here as well.


----------



## Nostradoomus (Aug 24, 2020)

I see lots of cold/suspect joints there.


----------



## dlazzarini (Aug 24, 2020)

Jared said:


> Sadly, I don't have an extra opamp available to try, though I'm not opposed to purchasing one if I need to. Thanks a lot for taking a look at that.


I doubt that’s what the problem is I just figured if you another it wouldn’t hurt to try. Now that you’ve posted pics I’d have to agree with nostradoomus. I would reflow a lot of those joints and clean your board with iso for starters.


----------



## Jared (Aug 24, 2020)

zgrav said:


> Can you explain what you mean here:  "I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through "
> 
> Is your test a digital multimeter?  Or are you using an audio probe?  A DMM is good for testing your connections between parts on a PCB, but won't let you test "through" a part unless it is a resistor (and then it would measure the value of your resistor, assuming no other parts connected those two points).
> 
> Have you tried an audio probe?  Easy to assemble from things you probably already have, and it will let you find out where your audio signal is being stopped.  You can search on google for building an audio probe, and find a number of posts in the forums here as well.


Thank you for the advice!
I made an audio probe by instruction from a video I saw on YouTube. That’s what I used to trace the signal.


----------



## Jared (Aug 24, 2020)

Nostradoomus said:


> I see lots of cold/suspect joints there.
> 
> View attachment 5981


Thank you! I will try to fix that. This photo really helps.


----------



## Jared (Aug 24, 2020)

C


dlazzarini said:


> I doubt that’s what the problem is I just figured if you another it wouldn’t hurt to try. Now that you’ve posted pics I’d have to agree with nostradoomus. I would reflow a lot of those joints and clean your board with iso for starters.


Cool, I will start there! What exactly is iso?


----------



## Jared (Aug 24, 2020)

dlazzarini said:


> I doubt that’s what the problem is I just figured if you another it wouldn’t hurt to try. Now that you’ve posted pics I’d have to agree with nostradoomus. I would reflow a lot of those joints and clean your board with iso for starters.


I’m guessing the alcohol?


Jared said:


> C
> Cool, I will start there! What exactly is iso?


----------



## zgrav (Aug 24, 2020)

you are right about iso --- isopropyl alcohol


----------



## Jared (Aug 25, 2020)

Nostradoomus said:


> I see lots of cold/suspect joints there.
> 
> View attachment 5981


I cleaned up the solder joints. It seems like some are still a bit rough but I think it’s because some of the wires are stranded and became a bit frayed when pushed through the joint. I also cleaned the PCB with iso.

There is still no signal. I used an audio probe as well. The result is the signal cuts out at the same point as before.


----------



## zgrav (Aug 25, 2020)

Using your schematic and the place you circled, is there sound on pin 1 of the transistor when you touch it with the audio probe?

If NO, do you have sound on pin 2?

If you do have sound on pin 1, do you have sound when you touch the audio probe to one side of C2?   If yes, do you have sound on the other side of C2?

Do you have sound on one or both sides of  R7?

If you use your DMM to measure resistance, what is the resistance you have between Q1, pin 1 and each side of R7?


----------



## Jared (Aug 23, 2020)

I’m working on a Wonder Drive pedal. I got it all built out and I’m not getting signal through the pedal when the switch is on.
I’ve checked for solder bridges, and made sure all polarity in the separate components are correct.
I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through; it’s after the first transistor in the signal. I’ve switched out transistor and the same thing is happening. No signal is coming out of pin 1 and progressing to the next resistor. 
I’ve attached a picture to help visualize. (Green is good to go, red is where the signal stops)
Any help would be greatly appreciated!
Thanks!


----------



## Jared (Aug 25, 2020)

Thank you so much for the inquiry! Here are my answers:

*-I don't have any sound on pin 1 from Q1, but I do have sound on pin 2.

-I have NO sound on C2 for (either side). 

-I have NO sound on R7 (either side). 

-My meter is reading 10k between Q1, pin 1 and one side of R7 is reading 10k while the other side is reading 0. *


----------



## zgrav (Aug 25, 2020)

do you get an voltage reading on pin 3 for Q1?


----------



## Nostradoomus (Aug 25, 2020)

Make sure there are no strays wires shorting each other out in these areas here. Best practice with stranded wire is to twist the end up tight, tin it with solder so it stays together, then feed it through and solder it in.


----------



## Jared (Aug 25, 2020)

zgrav said:


> do you get an voltage reading on pin 3 for Q1?


Im reading .03 volts for pin 3 on Q1


----------



## Jared (Aug 25, 2020)

Nostradoomus said:


> Make sure there are no strays wires shorting each other out in these areas here. Best practice with stranded wire is to twist the end up tight, tin it with solder so it stays together, then feed it through and solder it in.
> 
> View attachment 5988


Thank you. I actually went through and cleaned that all up and made sure nothing was shorting out along with when I went through and re-flowed the rest of the solder joints.


----------



## zgrav (Aug 25, 2020)

try removing Q1 and measuring the voltage you are getting in the socket for pin 3.  Is it still 0.03?


----------



## Jared (Aug 25, 2020)

zgrav said:


> try removing Q1 and measuring the voltage you are getting in the socket for pin 3.  Is it still 0.03?


Voltage is 0.03 coming from the socket for pin 3 if I remove Q1.


----------



## zgrav (Aug 25, 2020)

Look at the schematic and you can see that power should be coming through the 1N5817 diode and connecting to pin 3 of Q1.  See if you have power at the diode.  If you do, figure out why it is not reaching Q1 pin 3.


----------



## Jared (Aug 25, 2020)

zgrav said:


> Look at the schematic and you can see that power should be coming through the 1N5817 diode and connecting to pin 3 of Q1.  See if you have power at the diode.  If you do, figure out why it is not reaching Q1 pin 3.



I’m reading that I have power at the diode (I noticed that the voltage is reading negative on my meter, even at the power jack. I’m not sure what difference this makes).
From the diode, the power immediately goes to -0.03 volts when connecting to C11. Then from there it remains -0.03 volts when connecting to IC pin 8.
If I trace the back of the PCB, it seems Q1 pin 3 is connected to IC pin 8 where the power is -0.03 volts.
I’ve attached photos for reference.


----------



## zgrav (Aug 25, 2020)

If you have your probes on the meter oriented correctly, it makes a lot of difference if you get a positive or negative voltage.  Make sure you have a positive voltage on your PCB at the top beside the LED.  If that is negative you need to switch the wires at your DC jack.


----------



## Jared (Aug 25, 2020)

zgrav said:


> If you have your probes on the meter oriented correctly, it makes a lot of difference if you get a positive or negative voltage.  Make sure you have a positive voltage on your PCB at the top beside the LED.  If that is negative you need to switch the wires at your DC jack.


I believe the probes on my meter are mounted correctly (photo attached). If I meter the AC adapter directly, it reads positive voltage. When I meter the voltage at the top of the PCB it reads negative. If I switch the wires at the DC jack the pedal does not power on (LED does not light up). But it does seem to turn on when I have the wires oriented in the way that reads a negative voltage.


----------



## zgrav (Aug 25, 2020)

If you check the + and - wires at your PCB do you get a positive voltage?  You should.  If you get a positive voltage at the + pad, check the voltage on pin 3 of Q1 and see what it is.    If you are getting voltage there, you should check and see if the pedal is working even if the LED is not lighting up.  There is a chance that the power was the only issue.  And even if you still don't have sound, you can use your audio probe to see if you are now getting sound on Q1, pin 1.

In any case, if you change the wires coming from the DC jack and get a positive voltage on Q1, pin 3, swapping the leads on your LED should get it to light up when the board is powered on.


----------



## Jared (Aug 25, 2020)

zgrav said:


> If you check the + and - wires at your PCB do you get a positive voltage?  You should.  If you get a positive voltage at the + pad, check the voltage on pin 3 of Q1 and see what it is.    If you are getting voltage there, you should check and see if the pedal is working even if the LED is not lighting up.  There is a chance that the power was the only issue.  And even if you still don't have sound, you can use your audio probe to see if you are now getting sound on Q1, pin 1.
> 
> In any case, if you change the wires coming from the DC jack and get a positive voltage on Q1, pin 3, swapping the leads on your LED should get it to light up when the board is powered on.


Switching the +\- wires at the top of the PCB along with the leads to the LED seemed to clear up the voltage issue. Which is interesting because my DC jack is not labeled and I was told that the short connection point is supposed to be (-) but if it works properly, I have the short connection point as (+) (photo attached [wires are temporarily connected])

The audio signal still does not pass through the pedal when the pedal is switched on. I have attached reference photos.


----------



## Nostradoomus (Aug 25, 2020)

What kind of power supply do you have?


----------



## Jared (Aug 25, 2020)

Jared said:


> Switching the +\- wires at the top of the PCB along with the leads to the LED seemed to clear up the voltage issue. Which is interesting because my DC jack is not labeled and I was told that the short connection point is supposed to be (-) but if it works properly, I have the short connection point as (+) (photo attached [wires are temporarily connected])
> 
> The audio signal still does not pass through the pedal when the pedal is switched on. I have attached reference photos.





zgrav said:


> If you check the + and - wires at your PCB do you get a positive voltage?  You should.  If you get a positive voltage at the + pad, check the voltage on pin 3 of Q1 and see what it is.    If you are getting voltage there, you should check and see if the pedal is working even if the LED is not lighting up.  There is a chance that the power was the only issue.  And even if you still don't have sound, you can use your audio probe to see if you are now getting sound on Q1, pin 1.
> 
> In any case, if you change the wires coming from the DC jack and get a positive voltage on Q1, pin 3, swapping the leads on your LED should get it to light up when the board is powered on.


Better quality


----------



## Jared (Aug 25, 2020)

Nostradoomus said:


> What kind of power supply do you have?


I’m using a universal power supply for testing. You can switch out the connectors. I believe I have it oriented correctly.


----------



## Nostradoomus (Aug 25, 2020)

That’s positive ground...you’ll want to flip that and rewire your dc jack the other way around. Might need to replace your 1n5817 too.


----------



## Jared (Aug 26, 2020)

Nostradoomus said:


> That’s positive ground...you’ll want to flip that and rewire your dc jack the other way around. Might need to replace your 1n5817 too.
> 
> View attachment 6001


Thank you for the insight!

I flipped it and changed the DC jack around. Everything is reading positive. 
The power to the 1n5817 is reading 9.28v. Should it still be replaced?

I am still not getting audio signal through the pedal when the switch is on. I’ve attached a couple of pictures for referencing where signal can be heard.

Some things of note:
-all of the points where I’m getting signal are only on one pin accept for R5, the IC, and Q1 (Q1 = pin 1 and 2 are clean signals, pin 3 is distorted)

-Only pin 3 and pin 8 are getting signal for the IC. (3 is clean 8 is distorted)


----------



## zgrav (Aug 26, 2020)

if you are reading 9.28v on one side of the in5817, what is the reading on the other side?

look at the schematic and figure out where the connections from the in5817 are supposed to go (to a specific part, transistor pin, or IC pin -- not through that part to somewhere else).   Your next step is to make sure power is actually going where it is supposed to in the circuit -- use you DMM to see if the power is actually reaching each of those places, and note what the readings are at the transistor legs and IC legs.   

after you do that with the power, do the same thing making sure you have connections to ground everywhere you are supposed to.

after you confirm those things you can start using the audio probe again to see if you are making progress.


----------



## Jared (Aug 26, 2020)

zgrav said:


> if you are reading 9.28v on one side of the in5817, what is the reading on the other side?
> 
> look at the schematic and figure out where the connections from the in5817 are supposed to go (to a specific part, transistor pin, or IC pin -- not through that part to somewhere else).   Your next step is to make sure power is actually going where it is supposed to in the circuit -- use you DMM to see if the power is actually reaching each of those places, and note what the readings are at the transistor legs and IC legs.
> 
> ...


If you dont mind me asking, On the schematic, how exactly can I tell that something is supposed to be connected to the in5817? Does the VCC indicate this?

Also, I CAN tell what is supposed to be grounded by looking at the schematic, but I'm not exactly sure how to CONFIRM that it is being grounded.


----------



## Jared (Aug 23, 2020)

I’m working on a Wonder Drive pedal. I got it all built out and I’m not getting signal through the pedal when the switch is on.
I’ve checked for solder bridges, and made sure all polarity in the separate components are correct.
I’m using a tester and going through the circuit and I’ve come to the point where the signal does not pass through; it’s after the first transistor in the signal. I’ve switched out transistor and the same thing is happening. No signal is coming out of pin 1 and progressing to the next resistor. 
I’ve attached a picture to help visualize. (Green is good to go, red is where the signal stops)
Any help would be greatly appreciated!
Thanks!


----------



## zgrav (Aug 26, 2020)

your hunch is right -- the VCC from the diode should connect to the other VCC parts shown on the schematic.

to test for ground, you DMM should show that all of the points marked ground are connected to one another, and they  should also show they are connected to the  ground pad on the pcb, and to the ground terminals on the in/out jacks.


----------



## Jared (Aug 26, 2020)

zgrav said:


> your hunch is right -- the VCC from the diode should connect to the other VCC parts shown on the schematic.
> 
> to test for ground, you DMM should show that all of the points marked ground are connected to one another, and they  should also show they are connected to the  ground pad on the pcb, and to the ground terminals on the in/out jacks.



To answer your first question: *the Power at the IN5817 is (+) is 9.28v and (-) is 9.00v*

All of the components that have a VCC indication on them on the schematic are as follows (with voltage readings):
*-Q1: pin3 (9.00v)
-Q2: pin3 (9.00v)
-R18: (9.00v)*


I'm sorry, I'm new to all of this and I'm still not completely sure if I understand how to confirm if something is actually being grounded as it should be.  But I went through the schematic and determined what components are meant to be grounded (indicated by the three line triangle icon) and then tested them with my meter. The results are as follows:
*-IN: 0.00v (both pins)*
*-R1: 0.00v (both sides)
-R7: 3.70v and 0.00v on the other side
-C10: 4.47v and 0.00v on the other pin
-R4: 0.00v (both sides)
-Volume: 0.00v (all pins)
-R21: 3.70v and 0.00v on the other side
-R10: 0.00v (both sides)
-OUT: 0.00v (both pins)
-SW: 0.00v*
*-C11: 9.00v and 0.00v on the other side*

On the schematic, the IC doesn't indicate that any pins are connected to the IN5817 by the VCC icon but here are the voltage readings anyway:
*-Pin 1: 4.47v*
*-Pin 2: 4.43v
-Pin 3: 4.49v
-Pin 4: 0.00v
-Pin 5: 4.47v
-Pin 6: 4.51v
-Pin 7: 4.49v*
*-Pin 8: 9.00v*

After metering I tried the audio probe once again and found that the signal still does not pass through the pedal the same as before.


----------



## Mcknib (Aug 27, 2020)

Your voltages look good, the voltages you're getting suggest everything in the power supply circuit is working now that the guys have helped sort your inverted power

I've read through your post as far as I can make out you're now getting audio up to pin 3 of the IC? you shouldn't be getting audio on pin 8 (power vcc) so I'm a little confused

Are you numbering the IC pins correctly from 1 top left dot down to 4 then up in a U shape 5 to 8

It might seem like a daft question but are you getting bypass signal we know audios going in but can't see your in and out jacks to make sure out is wired correctly

Anyway here's the main audio path to assist your probing anything coming from a voltage reference e.g. VREF or going to ground may affect audio but isn't part of the audio path, when probing try to probe on the component legs or pins if you can it's not always easy to get a good probe connection on the solder side 

Perhaps it's a good idea to re probe following the green trace and update us 

The schematic bottom left power section shows connections to the IC pins 8 (vcc) and pins 4 (ground) labelled OPA2604AP you'll see the small 8 and 4 all other pins should be vref half the vcc so as I say all good


----------



## Jared (Aug 27, 2020)

Mcknib said:


> Your voltages look good, the voltages you're getting suggest everything in the power supply circuit is working now that the guys have helped sort your inverted power
> 
> I've read through your post as far as I can make out you're now getting audio up to pin 3 of the IC? you shouldn't be getting audio on pin 8 (power vcc) so I'm a little confused
> 
> ...


This is very helpful information. Thanks you so much.
Answers to your questions/inquiries:
-yes I’m getting audio up to pin 3 of the IC and nothing after that as far as the audio chain goes. (photo reference attached)
-also, when using the audio probe, I’m getting distorted audio from pin8. It sounds like I have the distortion knob turned all the way up, but adjusting any of the pots does not effect the signal at all. This is also happening on a few of the other components in the power chain.

-I do believe that I am numbering the IC correctly. (Photo reference attached)

-I’ve attached photos of my IN and OUT jacks for your reference.


----------



## Jared (Aug 27, 2020)

Mcknib said:


> Your voltages look good, the voltages you're getting suggest everything in the power supply circuit is working now that the guys have helped sort your inverted power
> 
> I've read through your post as far as I can make out you're now getting audio up to pin 3 of the IC? you shouldn't be getting audio on pin 8 (power vcc) so I'm a little confused
> 
> ...


Also, something else that might be of note, when I probe IC pin6 or R9 and turn my amp up, I’m hearing some sort of (Vietnamese?) radio chatter. No joke.


----------



## Mcknib (Aug 27, 2020)

Your IC numbering is correct, still strange you shouldn't get audio on power or ground pins at least I've never come across it

With your voltages on the op amp being ok and assuming you took the voltage readings on the op amp pins and not the solder joints underneath, that would indicate it's good so hopefully something simple like it usually is

I'd make sure your op amp is located into the socket securely if it is, I'd take it out of it's socket and reflow the socket solder joints, as you say they still look a bit rough, just hold your iron on them for around 4 seconds until you see the solder flow onto the solder pad and socket pins, you want your iron temp to be around 400 C

Picking up radio signals isn't unusual in higher gain circuits, in your case more than likely because it's not yet shielded in it's enclosure


----------



## Jared (Aug 28, 2020)

Mcknib said:


> Your IC numbering is correct, still strange you shouldn't get audio on power or ground pins at least I've never come across it
> 
> With your voltages on the op amp being ok and assuming you took the voltage readings on the op amp pins and not the solder joints underneath, that would indicate it's good so hopefully something simple like it usually is
> 
> ...


Thank you for the suggestions!

 I did take my readings from the pins and not from the socket side.

I went ahead and reflowed all of my solder joints with the 4 second suggestion you gave me and I re-seated the IC.
The audio signal is still bypassing when I switch the pedal on. 
and the audio is still being cut off at the same place in the audio path, as well as distorted audio still being heard on pin8 of the IC.

Is it possible that I could have fried the IC when the power was inverted or something?


----------



## zgrav (Aug 28, 2020)

It is possible your IC is bad, but having the power the wrong way was not likely to harm it.  Your diode was blocking most of it.  Do you have another IC you can swap out to try?


----------



## Mcknib (Aug 28, 2020)

The fact your voltages on the IC look good would normally mean it's working but there is a lot going on at IC 1.1 you've got VREF on all 3 pins the only way to know for sure is to try another one

It would be interesting to know what your voltages are for pins 1,2 and 3 on the empty socket 

As you know an audio probe just gives you your problem area not what's faulty 

You've taught me something, it dawned on me I'd never actually probed pin 8 for audio it being the power pin so I tried it on a wrectifier build and low and behold I got audio at pin 8 on all 3 op amps

We live and learn so thanks for that!

I have had occasion where op amp voltages threw me on a phase 90 repair I got very high readings with the op amp in socket removed the op amp and got good readings on the empty socket so thought faulty op amp swapped it for a new one still got high readings 

Eventually I found a bridged resistor which was only active with the op amp in circuit 

It being an active device it must have made a connection when in circuit, me being a hobbyist I asked the site expert who said it was rare but theoretically possible 

So voltages may look good but don't rule out a component being dodgy or good


----------



## Jared (Aug 28, 2020)

I’m glad I could lead you to some knew information! 
Curious, is your signal distorted on pin8 as well?

Here are my readings on the empty sockets:
Pin1-4.54v
Pin2-4.49
Pin3-4.54v

I will replace the op amp and report back!


----------



## Jared (Aug 28, 2020)

zgrav said:


> It is possible your IC is bad, but having the power the wrong way was not likely to harm it.  Your diode was blocking most of it.  Do you have another IC you can swap out to try?


I will replace the IC and report back!


----------



## Mcknib (Aug 29, 2020)

Yeah I get a lower volume distorted tone, it was bugging my wee tiny brain so I had to try it 

Whilst you're waiting for your op amps I'd check the components in the feedback loop between pins 1 and 2 specifically the B100K dirt pot

As you can see it's wired as a variable resistor without powering the circuit set your meter to ohms place your meter probes on lugs 1 and 2 turn it and the readings should change fully counter clockwise lower resistance, clockwise higher resistance 

You won't get accurate readings with all the other series and paralell resistances in circuit but the pot readings should still change 

I saw a post recently, can't recall the circuit or details but the problem ended up being a component in the op amp feedback loop not 100% but I think it was a pot


----------



## Jared (Aug 30, 2020)

Mcknib said:


> Yeah I get a lower volume distorted tone, it was bugging my wee tiny brain so I had to try it
> 
> Whilst you're waiting for your op amps I'd check the components in the feedback loop between pins 1 and 2 specifically the B100K dirt pot
> 
> ...




nonsense! Your brain seems to be quite large.
Thank you for more great advice!

from my limited knowledge, the readings seems pretty good:
Dirt b100k= 0 - 102.7k ohm
Tight a50k= 0 - 46.7k ohms

R19= 9.95k ohms
R2= 1.50k ohms
R15 = 4.69k ohms

C7= 128.2k ohms
C1= 171.6k ohms


----------



## Jared (Sep 3, 2020)

I got a new OPA2604AP and everything works perfectly!

I'm thinking I must have fried the old one when I had the polarity inverted on my AC adapter. 

Thank you all for all of your wonderful insight. Ive learned so much through all of this.


----------



## Nostradoomus (Sep 3, 2020)

Glad it works! It’s a great feeling.


----------



## Mcknib (Sep 4, 2020)

Great good to hear it

Another good reminder of how voltages are indicators

Good one's don't always mean it's ok and bad one's don't always mean it's fried

I think you did a good job with the info you provided especially with it being rare ish to get good voltages from a fried op amp 

I'm sure you'll get many more eureka moments 

That's why I love this addiction....er I mean hobby


----------



## Jared (Sep 4, 2020)

Nostradoomus said:


> Glad it works! It’s a great feeling.


Yes sir it is!


----------



## Jared (Sep 4, 2020)

Mcknib said:


> Great good to hear it
> 
> Another good reminder of how voltages are indicators
> 
> ...



Addiction indeed!
Thank you for all of the info YOU provided! It helped so much.

recommend any good phaser PCBs?


----------

