Hello,
I've finished this pedal and the feedback knob don't work, all others work normally. I have just one repeat in all positions of the fdbk knob. PT2399 chip work well I've tested it on other pedal. Here is pictures and one video of this problem. I have the 2015 version.
https://www.youtube.com/watch?v=IUHJdN0plAw
(http://imageshack.com/a/img921/2435/Bhx6aM.jpg)
(http://imageshack.com/a/img922/4233/1PKRdS.jpg)
My voltages:
IC1:
1,48
2,81
2,63
0
3,9
3,96
3,92
8,2
IC2:
5
2,48
0
0
2,74
2,48
0,62
0,68
2,49
2,49
2,49
2,49
2,49
2,49
2,49
2,49
IC3:
Varies
3,88
4,02~4,07
0
3,88
4,07
4,04~4,09
8,17
IC4:
3,92
3,9
1,93
0
3,8
3,92
3,92
8,2
Thank you for all.
Have you tried different2388s? Also, I'd reflow everything and check for solder bridges. Some of the joints look solder starved.
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One repeat means your delay is definitely getting out but it is dying somewhere between R30 and R4. Those resistors look correct on your build, so I would have another look at your Feedback pot. Probably best to audio probe it at lugs 3 and 2 and see if you are getting signal through. If not, something is amiss in the pot.
Might not help that the Fdbk pot is soldered directly to the PCB..... backwards.
Quote from: Govmnt_Lacky on November 15, 2016, 07:34:44 PM
Might not help that the Fdbk pot is soldered directly to the PCB..... backwards.
He makes a very valid observation.
Indeed. Did not even notice that.
Thanks for all help, I soldered it directly in the board because I had suspected that this pot was not working them I tested it and soldered again directly to the board. I was testing with audio probe and when I put in the pin 2 the signal pass but when I try in pin 3 it not work. I will try another potentiometer now and latter I will post the results .
Thanks
Quote from: madbean on November 15, 2016, 06:25:32 PM
One repeat means your delay is definitely getting out but it is dying somewhere between R30 and R4. Those resistors look correct on your build, so I would have another look at your Feedback pot. Probably best to audio probe it at lugs 3 and 2 and see if you are getting signal through. If not, something is amiss in the pot.
You were correct, the problem was the fdbk pot, I had tested it before solder in the circuit but unfortunately something happened when I solder it.
Now the pedal is working correctly and sounding awesome! Thanks for all help guys!