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Hey Brian,

Just got finished with the build. Thanks for the great project. Just wanted to point out that the wiring diagram as it is in the pdf has the "Out" and the "J2" switched. I wired up according to the updated diagram, and although it produced the effect when engaged, there was no sound when bypassed. Switched the positions of "Out" and "J2" and everything worked perfectly. That's to say out from the pcb to the top right of the 3PDT and output jack to the middle right of the 3PDT. Thanks again!

Jake

Going through the circuit with an audio probe showed all the noise originating from R5 to R6 and onward. I double checked the values and I have the right components in the right place. Seems kind of strange. I figured I'd go through with the probe before doing anything else, but I didn't expect to find the noise that early in the circuit.

Thanks so much! The hFe on the 2N3904 (Q1) is 282. Voltages are E ~4.2 B ~4.9 C ~10.3. The hFe on 2N5087 (Q2) is 400. Voltages are E - 10.3 B - 6.1 C ~ 1.2.

Looking at the schematic shows that pin 7 of IC5 is disconnected, with both inputs grounded. It will not make a difference. So the circuit should be OK.

Can you also measure the transistor pins?

Something I just realized is: You are powering it at 10v. BBDs are very sensitive to bias. When I say very sensitive, I mean less than 1V can make a huge difference.

First: The Bias of the BBD is still at 4.8V (pin 3 IC2) and the output is at 4.2v (pins 7 and . What does the document say about using other voltages? There is at least one change that is necessary (R13). I only ever seen this pedal powered with 9v or 12v, never 10v. You may have to change R13 to something between.

Second: The bias of 4.8v is probably for 9.4v (as stated in the document). That means: 10.3/9.4*4.8 = 5.3v.  I would start there. If you cannot get there, try reducing 82k. Some people even suggest that it is not necessary and may only reduce the ability to change the bias.

Do you have an oscilloscope?
If you do not have one, turn the bias trimmer until there is no flanging on one side, and then turn it the other way around until there is no flanging. Mark this two points, there is a high chance that the ideal bias is exactly in the middle. You can then fine tune with your ears.

Flanging is more pronounced with the feedback on max., but then you cannot hear the original repeat clearly. Try with the feedback at min. too.

Trimmer T1 also changes the feedback. See how it sound when it is at the lowest setting. You don't want the loud oscillations now. 

Is the filter matrix position working? I think it is easier to test everything with the LFO setting, and with the rate pot at half way, where the flanging occurs slowly. 

The clock trimmer should be adjusted so that you have a weird chorus like sound at half of the way and a normal sound on the other. In one direction it will go deeper into chorus territory and have lots of hiss, too much to the other side and you end up not having the flanging, because the clock is too fast and you are into that territory where it sounds kind of dry.

I think in filter matrix mode there is no LFO, so you are at a fixed clock setting. Try measuring pin 3 of IC4 or pin 7 of IC6.
By the way, do not use the voltages in the document as a reference for setting the trimmers (you can multiply them by the same factor 10.3/9.4 I used, to see how they should look like)

Last but not least, BBDs can be noisy. Hiss is normal at some settings.

PS: I was writing this, when I saw your update. I think the noise is incorrect bias+wrong adjustment of the trimmers and not a bad transistor or leaking cap.

Hey Thomasha,

I can take transistor voltages and report back when I get home this evening.

Regarding my 10v of power, I'm really not sure why that's happening seeing as how I'm using a 9v power supply (a standard boss style power supply and then a 9v port of a truetone one spot power supply with the same result).

I forgot to mention earlier in the thread that I took madbean's note about R10 and replaced 82k with a 1k. I've since removed and soldered a jumper, however it made no discernable difference.

The issue doesn't seem to be improper biasing (at least not only that) as there is no setting with the trimmers that results in no noise. If the effect is engaged there is noise/hiss/wooshing/distortion no matter where the trims are set or the combinations of the trims. The noise intensifies when the bias trim is set in what would likely be the "right" spot, but there is always noise.

I think zerro's mention of the low pass filter needing some attention is a good road to go down next. However, as I'm new to reading schematics, I'm not entirely sure where to find the low pass filter or which particular components are making it up. Any help with that would be greatly appreciated. I hate that I need someone to walk me through that at such a granular level, but that's the way it's got to be right now haha. I also have some new transistors and a couple new 3007s on the way to try out just in case. Thanks again! Sorry it took me so long to reply.

I replaced Q1 several times with no change in noise. I should try replacing C9 and C6 now? Thanks for the help.

[7.8 -- 0]

Welp. I don't know what happened, but I retook measurements and everything is pretty close to what it should be with the exception of pin 7 on IC5. Mine is at 0. The rating of my power supply read 10.35. Here are the voltage readings now:

IC 1
1. 4.5 -- 5.2
2. 4.5 -- 5.2
3. 4.1 -- 4.7
4. 0 -- 0
5. 4.5 -- 5.04
6. 4.5 -- 5.09
7. 4.5 -- 4.9
8. 9.1 -- 10.06

IC 2
1. 9.1 -- 10.06
2. ~ 4.4 -- ~ 5
3.~ 4.8 -- 4.7
4. 41mV -- .22
5. 0 -- 0
6. ~ 4.4 -- ~ 5
7. ~4.2 -- ~ 4.2
8. ~4.2 -- ~ 4.2

IC 3
1. 9 -- 10.05
2. 4.5 -- ~ 5
3. 4.5 -- ~ 5
4. 4.5 -- ~ 5
5. 4.5 -- ~ 5
6. 4.5 -- ~ 5
7. 4.5 -- ~ 5
8. 0 -- 0
9. 4.5 -- ~ 5
10. 4.5 -- ~ 5
11. 4.5 -- ~ 5
12. 4.5 -- ~ 5
13. ignore
14. 4.5 -- ~ 5
15. 4.5 -- ~ 5
16. ignore

IC 4
1. 4.5 -- ~ 5
2. 4.5 -- ~ 5
3. varies
4. 0 -- 0
5. 4.5 -- ~ 5
6. 0 -- 0
7. 0 -- 0
8. 0 -- 0
9. 0 -- 0
10. 0 -- 0
11. 0 -- 0
12. 9 -- 10.05
13. 0 -- 0
14. 9 -- 10.05

IC 5
1. varies
2. ~ 4.2 -- ~ 4.6
3. varies
4. 9 -- 10.03
5. 0 -- 0
6. 0 -- 0
7. 7.8 -- 0
8. varies
9. varies
10. varies
11. 0 -- 0
12. ~ 4.2 -- ~ 4.7
13. ~ 4.2 -- ~ 4.7
14. varies

IC 6
1. 0 -- 0
2. varies
3. varies
4. 0 -- 0
5. 9.1 -- 10.06
6. 9.1 -- 10.06
7. varies
8. 9.1 -- 10.06

IC 7
1. 4.5 -- 5.02
2. 4.5 -- 5.02
3. 4.5 -- 5.02
4. 0 -- 0
5. 4.5 -- 4.98
6. 4.5 -- 5.02
7. 4.5 -- 5.02
8. 9 -- 10.06

When the effect is bypassed I get a clean guitar signal, but when it's engaged I get lots of white noise / whooshing. However, I also get my guitar signal and can achieve some flanging when turning trimpots. Just need to get rid of the noise and I might actually have this thing ready to go. Any ideas? And thanks for the help so far.

The reading at the power jack was reading around 10v. I'm not sure I understand the rest though.

EDIT: Please see my updated voltage readings and description of the issue lower in the thread. The pictures are still in this original post. Thanks!

Hello All,

I'm having issues with my Current Lover build. I think I have all the proper components, I've checked the orientation of electrolytics, diodes and ICs, I've re-flowed the solder and I'm fairly certain my wiring is okay. So, I've taken voltage ratings of all the ICs and there are definitely problems. Unfortunately, I'm not too capable of telling exactly what is causing the problems. I'd appreciate some brighter minds than mine taking a look. Thanks!

https://www.madbeanpedals.com/projects/_folders/FilterMod/pdf/CurrentLover_2015.pdf

https://imgur.com/a/63xcEfB

I'll list the proposed measurements and my measurements to the side.

IC 1
1. 4.5 -- 5.2
2. 4.5 -- 5.2
3. 4.1 -- 0
4. 0 -- 0
5. 4.5 -- 0
6. 4.5 -- 1.1
7. 4.5 -- 4.9
8. 9.1 -- 10.2

IC 2
1. 9.1 -- 10.2
2. ~ 4.4 -- 4.2
3.~ 4.8 -- 0
4. 41mV -- 0
5. 0 -- 0
6. ~ 4.4 -- 4.2
7. ~4.2 -- .07
8. ~4.2 -- .07

IC 3
1. 9 -- 9.9
2. 4.5 -- 4.3
3. 4.5 -- 3.6
4. 4.5 -- 3.6
5. 4.5 -- 3.4
6. 4.5 -- 3.6
7. 4.5 -- 3.37
8. 0 -- 0
9. 4.5 -- 3.6
10. 4.5 -- 4.3
11. 4.5 -- 3.6
12. 4.5 -- 4.3
13. ignore
14. 4.5 -- 3.6
15. 4.5 -- 4.3
16. ignore

IC 4
1. 4.5 -- 3.4
2. 4.5 -- 3.4
3. varies
4. 0 -- 0
5. 4.5 -- 3.4
6. 0 -- 0
7. 0 -- 0
8. 0 -- 0
9. 0 -- 0
10. 0 -- 0
11. 0 -- 0
12. 9 -- 0
13. 0 -- 6.7
14. 9 -- 9.8

IC 5
1. varies
2. ~ 4.2 -- .11
3. varies
4. 9 -- 9.9
5. 0 -- 0
6. 0 -- 0
7. 7.8 -- 0
8. varies
9. varies
10. varies
11. 0 -- 0
12. ~ 4.2 -- .11
13. ~ 4.2 -- 0
14. varies

IC 6
1. 0 -- 0
2. varies
3. varies
4. 0 -- 0
5. 9.1 -- 10.4
6. 9.1 -- 10.4
7. varies
8. 9.1 -- 10.4

IC 7
1. 4.5 -- 5.2
2. 4.5 -- 0.17
3. 4.5 -- 1.7
4. 0 -- 0
5. 4.5 -- 0
6. 4.5 -- 5.2
7. 4.5 -- 5.2
8. 9 -- 10.4

When the effect is bypassed I can hear the high pitched "airplane taking off" sound, and when the effect is engaged there's a terrible high pitched squeal. Any help is greatly appreciated!