Engineer's thumb not working

    Hello all, I'm new here and I've completed my first kit (Engineer's Thumb) yesterday. I can solder but I'm not good at understanding electronics.
    I've been careful with polarities for diodes and condensers, checked if my solders were fine and really thought I did well. I can't see any short circuits.

    Plugged the pedal:
    I get signal but very faint, I have to push the level knob all the way up (still lower than bypassed sound), which brings a lot of noise (too much for this low noise pedal).
    Other knobs: no noticeable effect except some strange noise at some point when I play with the attack knob.

    Main led lights up, bypassed sound is full and clean, so I guess the problem is somewhere on the main pcb.

    Ih ave no idea where to start, any ideas? I will get a multimeter in the next days.
    And where can I hope to find a list of dc values I should expect on my pcb?

    Cheers!

    Same procedure as always :S :cursing: Standard procedure is just a thread away ;)
    But however - welcome to MD Forum

    1. RTFM

    2. Post the circuit / instructions

    3. Doublecheck orientation and value of every part

    4. Doublecheck fitting if transistor and ICs

    5. Check your Solderpoints. Point have to have a connection from front to backside - fillup the hole / full contact.

    6. Check your overall Offboard wiring (Jack, Foot switch)

    7. Make sure that you‘ve installed the rubber pads on the back side of your pots as isolation to avoid short circuits.

    8. Voltage measuring of Transistor´s and integratet circuits?

    Oops sorry. Yes right after posting this I went through the previous post and realized I should have taken time to "know the rules".

    Thanks anyway for welcoming me, and many more thanks Smellslikebleach, I don't know why I went wrong with C1 and C5. I fixed it a few minute ago and I now have a 100% operational and gorgeous pedal (or so far so good, should I say).
    Which makes me want to order more pedals and do better next time.
    Voltage and ground wire resoldered as well.
    Hendrixianer, I don't know what the actual transistor is (no number on it), but the schematics and component list both say BC327, so since the pedal is working fine I expect it to be the right one.

    Also I realized I swapped two 1M pots (ratio and threshold) thinking they were identical, I forgot there were log and linear pots. But that can wait as I don't think sound quality is affected.

    Thanks again and greetings from France,
    Michel

    Hi @meinherr and welcome to the forum,
    although @smellslikebleach is right regarding schematics and so on, in comparison to other first-posters, you did very well!

    Zitat von meinherr

    I forgot there were log and linear pots. But that can wait as I don't think sound quality is affected.

    The sound will not be affected, but if I were you I would change them anyways as I know I would else procrastinate it to the end of time ;)

    I also got the engineers thumb and I have to say its a very useful tool. But however, I have something I didn't do for too long already which is to label all pots properly. Without labels on the pedal I always have to look up which pot does what. I really have to fix this ;)

    @simon.bethke, you have a point, I'm an expert procrastinator whose world is already populated with things that are almost finished, so let's fix this pot thing.
    As for the labels, the graphics are ready, I'm just waiting for the postman to drop the decal sheets in my mailbox. :)

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