Friday, 1 September 2023

Pearl FG-01 Flanger

 Schematic is avaiable HERE.



15 comments:

  1. Finally got this finished but no joy. I have a clean sound and can hear a faint flanger type whoosh in the background. I've tried checking over the schematic but its pretty confusing so I think I'll leave this to someone else.

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  2. Had another check through the schematic but can't find anything wrong. I think I will come back to this at a later date, that schem is pretty big

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  3. Still fighting with this one, the Madbean document is very handy for voltages and the schematic is much clearer (albeit slightly different).

    I did find a couple of errors; the 4n7 at O4 needs to go to ground (I connected from O4 to M2), the 1M at L28 needs to go to ground (I connected from I28 to M27)

    Still doesnt work but I will get there!!!

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    1. Following this, as this Flanger pedal is highly recommended by some.

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    2. I gave up on this to be honest, I think it was my board as I checked the schematic a million times

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    3. I've had another crack at this but its still a no go. I've checked the schematic many times but cannot find any errors other than the ones in my first comment. I'll try an audio probe tomorrow and see what happens. IC3 and IC5 voltages seem a little off. IC1, IC2 and IC4 seem spot on, as do the transistors.

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  4. Hey Anders, we have a flanger. You can tag this pain in the ass bad boy - it works perfect now!!! There was a mistake on the schematic (pin 7 & 8 of IC 3 connected to 56K resistor to power rail instead of ground)

    So these are the changes:

    4n7 at position Q4 (not transistor Q4), move to ground on row M
    1M resistor at position L25 move to ground on row M
    56K resistor at position N23 moves to ground on Row M

    and there are only 68 cuts

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    1. What!?, Suddenly I'm able to login on my own blog!? Wohooo!!

      Big thank you Ian! This is awesome! May I ask you which BBD chips you are using? NOS or new? And where did you get them? My own stock have dried up and I'm eager to build this!

      The layout is updated and TAGGED!

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    2. Hi Anders, great to have you back.. I bought some BL3102 and MN3207 from Retroamplis a while back. I also bought some MN3102 and MN3207 from China on eBay and amazingly, they worked too.

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    3. Id love to know which exact China shop you got the working chips from. In fact, there should be a positive-list somewhere.

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    4. I tried the mn3102/mn3207 combo from Polida and was lucky, successfully tested in about 5 projects, I was also lucky with one mn3007 ordered from Polida too.

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  5. This comment has been removed by the author.

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    1. Hi mate, the LED does not flash - its just a bypass LED. Compare your voltages with the Madebean Kingmaker document

      https://www.madbeanpedals.com/projects/_folders/FilterMod/pdf/Kingmaker.pdf

      They should be pretty similar

      After that its just a case of using the trimmers to get the sound you want. The Madbean doc also explains how they work.

      Good luck - its a tough one

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  6. just had a second go at this one and its working, great work guys

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  7. Awesome sounding flanger, thanks for the layout! (Verified)

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