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I've soldered a stompbox for guitar and stuck into having no sound on the output. Visually I checked everything about the soldering and it seems good. As I am not so good at electronics I wish getting any help on how to step-by-step check the place where there could be a trouble using multimeter or some another methods. Schematic

UPD:Actual schematic

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  • \$\begingroup\$ Schematic where? \$\endgroup\$ – Ignacio Vazquez-Abrams Jul 12 '16 at 21:08
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    \$\begingroup\$ Post photos of the top & bottom of your actual board. Maybe someone will see a mistake. \$\endgroup\$ – brhans Jul 12 '16 at 21:08
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    \$\begingroup\$ The TL061 series needs a bipolar power supply. Its range is +/- 5 volts to +/- 15 volts. 9 vdc is not enough for this op-amp to even turn on and be stable. Check the datasheets. \$\endgroup\$ – VTNCaGNtdDVNalUy Jul 12 '16 at 22:07
  • \$\begingroup\$ This schematic is also missing bypass capacitors on the power pins of the op-amp. This is a poor design for a wide-band low noise op-amp. \$\endgroup\$ – VTNCaGNtdDVNalUy Jul 13 '16 at 0:44
  • \$\begingroup\$ @Sparky256 - Hi. Re "The TL061 series needs a bipolar power supply" - that doesn't seem to be the whole story; from TI TL061 datasheet, p15 "This device can be operated as a single supply operational amplifier [...]". Also "Its range is +/- 5 volts to [...]" is not such a clear lower limit. I have found old TI docs which state the lower limit is +/- 3.5 V (i.e. a single supply of 7 V) and an ST datasheet which shows +/-2 V in figures 3 & 6 on p7. Fully agree about the bypass caps, but [...] \$\endgroup\$ – SamGibson Jul 13 '16 at 3:14
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You should follow the signal path.

Start where you apply signal, the input, and check if there is the signal actually is what you expect.
Then follow the signal path and search where it disappear. Here is the fault.

Oscilloscope is a great help for this type of task.

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