Mid-Tom continous background tone

Discuss Yocto construction and related issues
  • Those are actually the conga's, not the toms
    Ground the switches ( viewtopic.php?f=16&t=720 ) and the noise will mostly vanish
    are you using an internal power supply?
    Get the latest unofficial Yocto V1 firmware here.
    Be sure to check the revised manual.
    Leave your comments in this thread.
  • I'm using a wall-wart type external powersupply. I will try grounding the switches. Thanks for the advice.

    The continuos tone is present on both mid conga and mid tom. In the sound file you can hear, when I switch from one to the other.
  • Grounding the switches did not improve the sound noticably. The constant mid tom/conga sound is still there.

    The low and high tom/conga were fine, even with the ungrounded switch housings.

    When I tap with the scope pin 7 of U17, I see a pretty strong signal, when not triggered. At the same point (pin 7 of U15) in the low tom/conga, there is silence.

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  • As Fabi303 guessed correctly in a chat conversation yesterday, one of the germaniun diodes is bad.

    The diode tester of my multimeter shows a value other than overload when testing against flow direction.

    Now I have to get some replacement diodes (some, because I also need some to build a distortion circuit).