Saturday, 8 July 2017

Systech Overdrive

Here is a simple layout for a nice pedal from the 70's.
The schematic I've used is available here.



27 comments:

  1. Thanks Alex. I was just looking at this thread and was about to try and make his vero a bit more compact. You saved me.

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  2. Yey. Almost started on this myself :) Will probably build myself one at some point.
    Nice work again Alex!
    +m

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  3. Thanks Alex, I have 15 pieces of Vero being delivered Monday so I know what I'm gonna do.

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  4. really cool pedal. The eq section seems a bit different . its on the long list ha ha love the harmonic energizer made. These guys do some really cool stuff with EQ very interesting. Now its on the short list ha ha

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  5. Man, that EQ control is begging to be sent out to an expression pedal ;)

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  6. Call it verified! Can't believe how cool a pedal this is. Highly recommend giving this one a go. Thanks as always Alex for your superb layouts.

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    1. Does it sound as raw and growly as the vid ?

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    2. Ah ! Next on my list then thanks 😊

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    3. Ok, built it, freaking awesome !!! And unique
      I love it ! Crazy crazy as BOC said below

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  7. Crazy, crazy pedal ! Built it with success and love ! Thanks again Alex for this jewel !

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  8. It does have the cocked wah sound for sure. It seems to really bring out some of the higher overtones as well. I think I also need to give this one a try. Really different.

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  9. Made this this morning. Really easy build for a pretty unique sound. Definitely recommended.

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  10. I think i need a little help, here...
    I built this one, everything works fine except that, when i let a note ring, it ends quite fast, like a "gate" effect with a quite unpleasant distorsion (something like "crrrrshrrr"... ;-)). Not problem when i play non-stop without leting the notes ring too long, but when i let one ring...
    I verified everything twice,changed the AOP and the transistors several times and with several othe rmodels, no difference, verified the values of the components but i can't find anything :-/
    Any idea ?

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  11. And here what i find after a few hours of tests, mesurements ans comonents replacements :

    - The ugly distortion aprears when i turn the "dito" knob up. Under 60% it's not audible but the pedal is not as funny :-) Disto all the way up, this distorsion is quite as important as the guitar sund itself.

    - I've got much less of this unpleasant distosion if i use a JRC4558D

    - "disto" all the way down, i haven't got any more sound is it normal ?

    - The pedal works quite the same with the 3904 soldered backaward. Normal ?

    - Here are my mesurements :
    5457 : D = 8,15V / S = 1,70V / G = almost 0V
    3904 : C = 5,48V / B = 1,90V / E = 1,31 V
    4558D : 1=4,0V / 2=4,0V / 3=4,0V / 4=0V / 5= 4,0V / 6= 4,0V / 7=4,0V / 8=8,1V

    Thanks again.

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  12. No idea anybody ? I don't find my voltage values strange, did i miss something ?

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    1. I'll check my voltages. You should open a thread in the debug section and post hi res pics of both sides of the board

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  13. Thanks. Oh, i'm absolutely sorry, i didn't notice there was a debug section. I'll post there immediately and thanks for the help !

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  14. Great layout (as always) and a great pedal! Exactly what I needed on my board, fuzzy cocked wah sounds with one stomp. I used a big knob for the EQ so I can turn it with my foot. I highly recommend this.

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  15. I am new to this, but what is the value of the CLR resistor?

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    1. It can be anything as low as 1k up to ?...most of the values I see people using is 4.7k or so. Lower the value the brighter the LED!

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    2. oh thats the resistor to keep the LED from blowing. I didnt know that you could increase it to make it dimmer, all my LEDs on my pedals are like spot lights. I am going to have fun fixing that tonight.

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    3. I left out a thank you, sorry about that.

      Thank you!

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  16. Hi guys! my two cents on that build - i've canged dist legs 2 and 3 and now on lower gain it cleans up better. You can get it almost clean or overdrive'y style that way and not only fuzz'y or distortion'y. In my build i will leave it that way :)

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  17. So I finally finished building this one and I keep getting what I can only label as a "crispy" sound after striking the note. Is this an indicator of a bad component? Did I wire something wrong?

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