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Current Lover needs lovin' (w/ pics and voltages)

Started by LateCentury, February 10, 2017, 07:28:47 PM

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LateCentury

This build went very smooth up until I decided to box it before I rocked it.  ::) The bypass signal is crystal clear, but when you kick it on it goes silent. I've quadruple checked that every wire is going where it needs to. The optional fx loop is connected the way its supposed to with the switch jacks. The LED lights up, but not the LFO LED. I would think that at least SOME sound would come through.




The close pic of the capacitors is showing a little hack I made to pull them back to make room for the fx loop jacks. I de-soldered them from the board, and re-soldered longer legs to those 3. The diode is not touching the legs and the LFO LED its not either. I don't know if that would matter.

Here are the voltages. The numbers in bold are the ones that appear massively different from the documentation.

Voltage at power jack: 9.31

IC1 4558
1. 4.66
2. 4.66
3. 2.32
4. 0
5. 4.53
6. 4.53
7. 4.39
8. 9.63

IC 2 MN3007
1. 9.03
2. 4.48
3. 0
4. 0
5. 0
6. 4.48
7. 2.56
8. 2.57

IC CD409
1. 9.02
2. 4.48
3. 4.47
4. 4.47
5. 4.49
6. 4.46
7. 4.49
8. 0
9. 4.47
10. 4.48
11. 4.47
12. 4.48
13. 0
14. 4.47
15. 4.48
16. 0

IC4 CD4013
1. 4.48
2. 4.48
3. 7.33
4. 0
5. 4.49
6. 0
7. 0
8. 0
9. 0
10. 0
11. 0
12. 9.03
13. 0
14. 9.02

IC LM324
1. .5~7.5
2. 4.02
3. 2~5
4. 9.01
5. 0
6. 0
7. 7.74
8. 1.03
9. 1.03
10. 0
11. 4.01
12. ~
13. 4.09
14. 3.5~4.5

IC6 LM311
1. 0
2. 4.96
3. 3.42
4. 0
5. 9.03
6. 9.03
7. 7.32
8. 9.03

IC7 4558
1. 4.51
2. 4.51
3. 4.51
4. 0
5. 4.01
6. 4.52
7. 4.52
8. 9.01

Thanks in advance! This is so frustrating!

BrianS

I am having similar problems with mine but I didn't box it up.  I will be watching this in hopes I can get mine running also. 

Jebus

Audio probe is always my go to -debugging method in cases like this. :)

Matt

So you don't get any signal no matter how you set the trimmers?  If so, yeah it's audio probe time
Matt

LateCentury

Quote from: Matt on February 11, 2017, 05:21:54 PM
So you don't get any signal no matter how you set the trimmers?  If so, yeah it's audio probe time

Yeah, nothing at all. I made an audio probe this afternoon (this one) and I got a little buzz on basically everything that I touched, except for the "R" lead and the output pad on the footswitch. If I'm reading the documentation correctly, the very next component in the audio path (from the output) is C15...? That made a sound too, so I don't know what I'm doing wrong here.

Matt

Matt

Govmnt_Lacky

Why does it look like D4's cathode (-) is shorted to C18's positive?

LateCentury

Quote from: Govmnt_Lacky on February 11, 2017, 08:52:00 PM
Why does it look like D4's cathode (-) is shorted to C18's positive?

Its not touching, kinda looks like it in the photos, but no.

LateCentury

Quote from: Matt on February 11, 2017, 07:44:33 PM
You are getting audio at c15? Or just buzzing

I plugged the audio probe straight into an amp and poked the points on the board. There's no audio when the pedal is powered up and switched on, so I'm getting only the buzzing from the amp or no buzzing when touching the output at the switch and "R" pad.

Is it correct to assume because I am hearing the amp buzzing at C15 that the audio signal is at least passing all the way through to that component? I don't know how to read the audio path on the drawing.

Matt

are you hearing the guitar at all when probing it just buzzing.

A couple things I'd check is that your output jack isn't grounding out and that your foot switch isn't bad
Matt

LateCentury

Quote from: Matt on February 12, 2017, 10:18:20 AM
are you hearing the guitar at all when probing it just buzzing.

A couple things I'd check is that your output jack isn't grounding out and that your foot switch isn't bad

Actually... I checked again and turned up the amp volume considerably and I CAN faintly hear guitar signal. When I hold my thumb on the output tip so its buzzing and touch the pad on C15, it gets much louder and I can hear the flange effect working. But its still not a full on guitar signal.

So, should I gather from this that its some kind of ground issue?

BrianS

One thing I do is hook my iPad or phone up to the effect when I'm using my probe.  Or you could download a signal generator.  Then you will have continuos sound going through and you don't have to keep hitting a guitar string.

Are you getting sound all the way up to C15?   

LateCentury

You know what... I don't think I'm doing the audio probe thing correctly. There must be more to it that I'm not getting yet.

BrianS

Ok.  Let's see if you are hooking it up correctly.  Your signal is going to the in jack of the effect (guitar, signal generator, etc...).  The probe phone jack is hooked into your amp and grounded to something.  There is nothing hooked up to the out jack of the effect.  The end of your probe acts as your out jack now, so to say. Not trying to insult your intelligence here so plse dont think that. 

If you want, take the cover off of one of your pedals that's works, hook it up as above, get a signal going through and probe around the board.  That will give you an idea of what you should be hearing. 

That's why I asked if you were getting sound up to C15. If you have no sound at R1 you will have no sound at C15.  So let's determine if you're getting signal to the board when you turn it on.  Thats the beauty of the probe.  If you can follow the signal path off the schematic you can quickly figure out where it stops and that normally will be where your problem is.


Scruffie

You have no bias voltage on pin 3 of the BBD so there's a problem around the R9/10 area.
Works at Lectric-FX