Friday, 16 September 2022

Beetronics WhoctaHell

 Schematic is avaiable HERE.



25 comments:

  1. Very interesting, looks like a Robot Devil in disguise

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    1. Compared the schematics and you're dead on - starve is removed and there's a few filtering caps added - other than that it's a dead copy

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  2. I'm having some problems here... i got it to literally fire up :D! i get some sound but, when fuzz is on 0 i got some sparks and the classic burnt plastic smell - it's been a while since i made fire on 9v! i also just listen to the 8bit sound. not like in the demos where it is more fuzzy... i'll keep checking what mistakes i made.anyone tried it? also some minor things: it's a 18x17 (wrong in the description) and why use a 3PDT? it can be a DPDT, right?

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    1. It looks like a 3pdt was chosen to include an LED indicator - you can use a DPDT on/on just omit the LED

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    2. even with the led, since it's connected to the board, we only use the first 5 lugs of the switch. that's the only part of my circuit that it's working well:D!

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    3. Look at PCB pdf, they use 3PDT, but one column is not connected at all, so DPDT is fine, or SPDT if you don't need that LED. I built this too, no fire, but no sound either. Failed to found the problem so far.

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  3. Hello,
    So it hasn't been verified yet, right?

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  4. This one is verified, and both circuits seem very similar : https://dirtboxlayouts.blogspot.com/2019/07/dwarcraft-devices-robot-devil-w-mods.html
    Unless i'm mistaken, it seems the IC wiring differs a bit?

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    1. The IC connections are the same, minus the addition of some 100nf caps - 4040s have 11 outputs, and 4049 has six hex inverters to choose from so it can look like different connections on a vero layout, but they're electronically equivalent.

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    2. Oh, thank you for your insight : I wasn't aware about that, and thought the ICs were wired differently...

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    3. I'm incorrect about the 4040 upon review - the pins do matter as they correspond to frequency divisions - but they're correct here - pins 7 and 9 - connected via switch just like the robot devil.

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  5. Maybe I'm showing my greenhorn here, but I found some differences -
    The schematic shows output comes from level 3, through the 1uf coupling capacitor - not level 2 - also - the 100k resistor on the very right should connect octave 2 and level 2 - and the 100k top row 15 should connect fuzz 2 and level 2. Everything else looks okay so far as I can tell

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  6. This comment has been removed by the author.

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  7. The 1 m resistor between output and ground should also be eliminated

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  8. So, basically, we should :
    1- swap level 2 & level 3
    2- remove the 1M resistor
    that's it?
    I should be able to try tomorrow (or in the next days), I will let you know how fine it works

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    1. That's all I can see different from the schematic currently - please let me us know how it goes! Thank you!

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    2. The 1m resistors are anti pop resistors before the input cap and after the output cap. They don't affect the performance of the audio circuitry in any way. I Should have mentioned that in the post.

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  9. Hello,
    So I just built it, and it kinda works : I get the distorted sound as expected, and the octave led indicator lights up when I rock the switch, but I don't hear the octave sound.
    I just finished the built, and haven't really closely inspected everything, so it can very much be an error on my side :)
    Maybe also it's my 4040, because i am unsure if it is buffered or not.
    Also, despite being an easy build, I noticed a couple things which could lead to wiring errors : there is an "octave" pot, an "octave switch" (-1/-2oct), and an "octave on/off" switch... So maybe i messed up a couple things here :)
    It's getting late here, so i won't get into any troubleshooting right now, but I will let you know tomorrow how things go :)

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    1. User error indeed (i used the wrong IC instead of 4040) :)
      You can tag it verified, it works as expected and sounds raw!

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    2. Thanks KG!
      I'll tag it ASAP.

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    3. Thanks to you, Fuzzhead ;)

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  10. I am really enjoying that octave-down pedal... THank you FuzzHead for another great layout!

    I'd have a couple questions about possible mods :
    1- Is there any way to increase output level a little bit? (it reaches unity gain, but i wish I could get a little more volume when needed)
    2- The distortion pot is a volume pot, not a gain pot, so it seems that the fuzz gain is fixed... Is there any way to add a fuzz gain pot (or toggle switch)?
    3- Is there any way to damp the sub octave square wave a bit? I tried with a Lowpass filter pedal after the Whoctahell, and it was great (less harsh, less robotic), so i am considering trying to add a simple fixed lowpass after the suboctaver...

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  11. is the distorted square noise supposed to sort of always be on? what I mean is if the strings on guitar are not being struck do you still hear a distorted signal? or should it be dead silent? I did the fixes suggest by Orion Tonehunt and it does sound better. however I'm not exactly sure what the spdt is doing.

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