Help needed: DIY Small clone chorus from tagboard effects, no chorus

[Doomster]

Hey guys (and girls??).

I have some problems with this build that I made using a vero model from tagboardeffects (http://tagboardeffects.blogspot.dk/2014/06/ehx-small-clone.html).
There is sound but now chorusing..

I have checked for the correct resistor value and everything is in order and in the right place, the same is true for caps. IC's, cuts, links, diodes and the trimmer.
I didn't have a 180 pF cap. so i used a 150 pF + a 30 pF cap instead.
I have checked for solder bridges and went over the coppor side with a stanley knife and scratched around just to be sure. No cold solders as well.

now to the "best part"  my readings is no way similar to other people with the same problem as I have read in other posts.

So please.. Before I smash this circuit with a sledgehammer... Please help me 

the readings are:

input voltage 9,18V.

4585
1) 4,94
2) 4,95
3) 3,94
4) 0,00
5) 4,78
6) 4,91
7) 4,88
8- 9,81

MN3007
1) 8,96
2) 3,85
3) 8,36
4) 0,00
5) 0,00
6) 3,57
7) 6,99
8- 6,99

CD4047

1) 9,05
2) 0,06 VDC
3) 7,92
4) 9,15
5) 9,15
6) 9,15
7) 0,00
8- 0,00 VDC
9) 0,00
10) 4,54 VDC
11) 4,54 VDC
12) 0,00
13) 9,06
14) 9,15

LM358

1) 0,00 VDC
2) 2,27
3) 1,95 VDC
4) 0,00
5) 4,09
6) 0,03
7) 2,12 VDC
8- 9,80

Q1 2N5087
C 0,00 B 9,58 E 8,42

Q2 2N5088
C 9,81 B 6,38 E 6,38

Q3 2N5088
C 9,80 B 9,53 E 8,93

[robthequiet]

When you combined your caps, are they in series or parallel?

[Doomster]

They are parallel. Mounted in the same holes. Should I make them in series instead?

[Dasher]

Hold that sledgehammer!

I compared your voltages to my own. The LM358 readings differ from mine. I would suspect that the LFO isn't working, thus giving you no chorus effect. Can you confirm that some of the LM358 voltages oscillate? Turning the depth pot all the way up and the speed pot all the way down will make it easier to see this on your multimeter.

Also, your Q1 voltages are different from mine. Not sure if they'd be a problem though. I have C=0, B=3.36, E=3.98.

Caps in parallel increase capacitance. They decrease capacitance in series. So 150pf + 30pf in parallel is correct if you want 180pf.

[Doomster]

I have tried different LM358 now but it does'nt make a big difference. Det oscallation is very very low when i check it with the multi meter. The readings on Q1 is way better since i shifted to another LM358. But i didn't get af reading on pin 6... Could this mean that i have a busted 2,2 uF cap?? Since it is the only component connected to this pin.

[robthequiet]

Any chance you could post a photo of the board close up so we can take a look?

[Doomster]

Will do ASAP. Both Sides??

[Dasher]

Both sides would help.

[Scruffie]

Why do pins 2 & 6 of your 3007 have such low voltage compared to the 4047's pin 10 & 11 which they connect to, you should check there.

[potul]

just a shot in the dark... but did you play with the trimmer? In my small clone, the range between no chorus and distortion is quite small.

Is the dry signal heard?

[Doomster]

I have been playing around with the trimmer and it have not helped. I have switced the lm358 and that have seem to changed the voltage between pin 10 and 11 of cd4047 and pin 2 and 6 on 3007. Thanks for the heads up; ) still no chorus though...

[Buildtestrepeat]

I really hope you can get this sorted, it's a nice effect.  Fortunately the only issue I had when I built this one was a bad diode behind Q1.  I found it after following up on bad voltages in that area so keep at it. 

[Doomster]

Potul: Yes the dry signal is loud and clear.

Buildtestrepeat: Thanks for the tip and "chin up" boost  I know this is a very delicate circuit.. and a mother' to trouble shoot.

Getting back to Dasher:







If the images are not sufficient please let me know and I'll snap some better ones.

[Yazoo]

Sorry if this is completely wide of the mark but I had a problem with a small clone build over Christmas and it was actually a faulty MN3007. I tried 3 suppliers on eBay before I got one that worked. Fortunately for me, I was building a second version and I was able to swap out the chip from one I knew worked correctly. I had the same problem as you, sound but no chorus effect.