Tonepad chorus ce-2 troubleshoot

[Chillums]

Hey there guys... I'm in need of a little help... I have a signal going through but no chorus.     here are the ic voltages if anybody sees anything weird let me know.... Thanks.   

IC1 4558
1  4.25
2. 4.25
3.  4.25
4   0
5  4.25
6.  4.25
7.  4.25
8   9.23


IC 2  TL022
1.   .65~8.66
2.    4.59~4.71
3.    2.3~6.6
4.    0
5.    4.59~4.71
6.    4.62~4.74
7.    2.7~6.5
8.    9.32

IC3. 3007
1.    5.26
2.    2.85~2.97
3.    3.52
4.    4.71
5.    0
6.    1.81~1.89
7.    2.46~2.49
8.    2.46~2.49

IC4  3101
1.    5.42
2.    1.82~1.91
3.    0
4.    2.86~2.96
5.    .28~.49
6.    4.62~4.87
7.    1.83~2.30
8.    4.67~4.71

Thanks again guys!!!  Ill deal with this thing in the morning.... 
I added a better ( but not great with the shadow and glare from the light on the flux) photo.... I will clean properly and take a better shot tomorrow.

[xorophone]

Hello! Have you tried adjusting the trim pot (while strumming your guitar)? There'll be no chorus applied if the trim pot isn't set right. At one part of the trim pot (probably around 12 o' clock) a distorted chorus signal will be applied. If you continue turning it after that point you should get a clean chorus signal.

To me it looks like you're getting an output from the MN3007 and I'm pretty sure the MN3101 is working as intended, since there's modulation on pins 4 and 2. Try audio probing IC3 pin 8 or 7 and if the signal has chorus applied, try following the path between IC3 pin 8 and IC1 pin 6 using your audio probe and find out where the signal dies. Remember that you won't hear anything on an op-amp's inverting input, which means IC1 pin 6 will be quiet even if the signal is reaching it. If you don't have an audio probe, check out this tutorial on how to make one: https://www.youtube.com/watch?v=jWvIfDSxbIk

If that doesn't work, I recommend reading my thread about a similar problem: http://www.diystompboxes.com/smfforum/index.php?topic=117794
In my case the MN3007 and MN3101 chips were fake, but I'm guessing that's not the case with your build. The beginning is unrelated to your problem, but read the conversation between me and robthequiet, try the things he's suggesting and then compare the results with mine. Give us the results in this thread.

Good luck!

[Chillums]

I'm not home right now to check but it looks like I bought the same 4 pack batch of mn3007 mn3101 too.  Just by looking at your pics they look identical.  Even the 3101 that looks like it has a sticker on it.  So I'm going to start by replacing the parts first and will report back once I have replaced both chips. Thankyou for directing me to your thread cause I would have never found it otherwise.  Do you remember who you bought the bunk chips from?   And did you ever get your money back?  Thanks again for your help!!!

[xorophone]

I'm not home right now to check but it looks like I bought the same 4 pack batch of mn3007 mn3101 too.  Just by looking at your pics they look identical.  Even the 3101 that looks like it has a sticker on it.  So I'm going to start by replacing the parts first and will report back once I have replaced both chips. Thankyou for directing me to your thread cause I would have never found it otherwise.  Do you remember who you bought the bunk chips from?   And did you ever get your money back?  Thanks again for your help!!!

To me it actually looks like your chips are working, so I suggest testing the circuit a bit more before you replace them. Try the things I wrote in my other reply.

I bought my chips from "New & Original" on AliExpress, which is kind of ironic. Without any hesitation they agreed to send me new chips from another supplier. I haven't received them yet, but they're here in Sweden, so they should be here any day now. The other chips I bought were from banzaimusic.com and they worked great.

So if you need to buy new chips I'd suggest buying them from Banzai or Smallbear (depending on shipping costs), but I really think you can get the effect working with your current chips.

[Chillums]

Ok cool.... When I get home tomorrow I will check the circuit with the audio probe and report back.  Did you end up using the the 022 or the 072 in your build?  Thanks again bro!! .

[xorophone]

Ok cool.... When I get home tomorrow I will check the circuit with the audio probe and report back.  Did you end up using the the 022 or the 072 in your build?  Thanks again bro!! .

I ended up using the 072 and it works great! I've considered buying an 022 just to see if it makes any difference, but it's only there to provide an LFO for the mn3101, so I don't think it would change the sound in any way.

No problem! I'll continue helping you until it's fixed.

[Fender3D]

To me it actually looks like your chips are working...

Sorry Anton, how can you state this?
Pin 1 does not get 9V
Pins 2 and 6 are way different for a proper clock...

Either R52 is not a 33R or MN chips suck too much current.

@Chillum:
check for a proper clock at BBD's pins 2 and 6

[Mark Hammer]

While it is important to measure and post voltages for/from chips, it bears noting that there are several transistors in the delay signal path, and that pinouts and orientations can vary across transistors.  It will be worthwhile to verify that that the pins you think are where they should be actually are where they should be.

[Chillums]

Ok so I used an audio probe and the signal stops at IC3 pin 3.    I can hear oscillation on ic4 pin 7 and on the pots.  There is a variable voltage on ic4 pins 5 and 7 and the voltage is the same on the cathode of D1.  If I turn the trimpot past halfway the signal gets distorted at IC3 pin 3 but and the voltage does change but nothing else....   I've checked the values five times and everything looks correct.  Flipped the transistors and nothing happened.   Bought the 5088s from mouser and checked the pinouts so they are correct too.   I'm not sure how to check for the clock on pins 2 and 6.    I'm assuming that is the mn3101?  I'm out of ideas other than buying new MN chips.   Just a note I have a 100k log pot instead of a linear one but that should stop the circuit from working right? J  I'm going to solve this!!

[Chillums]

Here's the voltages for the 5088s

Q1

E-3.0
B-3.4
C-9.2

Q2


E-3.2
B-3.7
C-9.2

Q3

E-3.1
B-3.5
C-9.2

Q4

E-2.6~4.1
B-3.4~5.0
C-5.2

Q5

E-0
B-0.3~.0.4
C-3.9~4.2

Does anybody know if these voltages look right?  I have new MN chips on the way but they prob won't get here till the end of the week or so..... The only thing to me that looks weird is Q5 with 0 volts on the emitter.  I'm betting on bunk chips....

[Fender3D]

Measuring 5088 is useless until you don't fix these:

3007's Pin 1 does not get 9V
3007's Pins 2 and 6 are way different for a proper clock...

Either R52 is not a 33R or MN chips suck too much current. (then dead)

check for a proper clock at BBD's pins 2 and 6 (you need an o-scope or a freq. meter capable to measure duty cycle)

[Chillums]

I get 9v all the way to R52 then it drops to 6v on the other side.... And I think your right... I never thought to check how hot they were getting but they were to hot to keep my finger on it.   So I would say that they are sucking way to much current.... What would cause that a broken chip or a fake chip?  Either way I'm ordering new chips from small bear this time.  Not from evilbay!!

[xorophone]

To me it actually looks like your chips are working...

Sorry Anton, how can you state this?
Pin 1 does not get 9V
Pins 2 and 6 are way different for a proper clock...

I guess you're right. I just quickly glanced over the voltages and assumed it was working since he was getting a signal on the output pins.

I get 9v all the way to R52 then it drops to 6v on the other side.... And I think your right... I never thought to check how hot they were getting but they were to hot to keep my finger on it.   So I would say that they are sucking way to much current.... What would cause that a broken chip or a fake chip?  Either way I'm ordering new chips from small bear this time.  Not from evilbay!!

I'm sorry for not posting here in a while. I've been extremely busy lately (and still am). I don't have time to read the latest posts right now, but at least I'm bumping the thread for you. I might have time to post some measurements from my working ce-2 clone in a few days. Even if the chips might be fake, it's probably good to rule out any other problems with the circuit before you put the new ones in, to make sure you don't break them.

[Chillums]

Ok cool....my chips won't be here till next week sometime so no rush bud.   Thank you for your time.

[Chillums]

Just wanted to update and say that it was the chips that I bought off EVILBAY!!!   They just got super hot....  Sucks that there are people out there selling fake chips.... Anyways.... bought a pair of mn3007/3101 from smallbear and it works like a charm.   Thanks to those who helped.