Eq for both bass and guitar?

[ghiekorg]

Hi guys,
i just did a first version of the layout. I checked it quickly and seems correct. I will check it again tomorrow though with a fresher head. It should fit nicely a 1590B placed in both orientations (the board will be around 48x28mm) with pots non board mounted



is C7 necessary if there is already C6?

Edit: i added a 4001. I never understood if a 4001 is always a good solution and it's used only to avoid damage in case of wrong polarity

[iainpunk]

is C7 necessary if there is already C6?

yes tis still necessary.

Do you think it will get better when boxed?

yes it will, the long breadboard wires are like radio antenna's for noise, this disappears when its on a circuit board and it disappears even more with a metal box.

looking over the layout quickly, i don't see any obvious mistakes, ill look it over more precisely later.
what kind of circuit board are you using? perf board/pad per hole?

cheers, Iain

[ghiekorg]

Thank you Iain,
i will actually etch it. Once double checked i will make a black and white printable layout.

[iainpunk]

very nice, good luck!
i do recommend socketing the IC's to transplant them if the layout turns out to be bad.
do you already have the dual pots?
waht is the latest schematic you have? asking for a friend (haha jk)

cheers

[ghiekorg]

I always socket ICs and transistors last time when i did the phase90 i socketed also the diode

The last schematic should be this (only the 4001 is missing)
I am NEVER sure about the pot lugs 1 and 3 orientation. As i breadboard it it should be like the orange number i placed on the schematic. I hope it's correct before soldering i think i will still double check it with clamps. I ordered the stuff today (i don't have the pots/knobs, the 1.5nF  and 33nF caps and the case), i hope to have them in 10 days or so.

[iainpunk]

good to hear! its wise to socket a lot of stuff. i once socketed a resistor, but that's a whole other story.

the 4001 in this configuration needs a low value resistor in series with the power connector to act as a fuse to not kill the pedal, if there is no such resistor, the diode will fail and then the whole circuit lets out the magic smoke! 100ohm is enough tho, no need to change the layout, you can just splice that resistor in line with the power wire and tape it or shrink wrap it to not short against anything, this makes it easier to replace if anything has gone wrong.

cheers, Iain

[antonis]

I am NEVER sure about the pot lugs 1 and 3 orientation.

Conventionally, Lug 3 faces voltage (potential difference) higher than lug 1..

[ghiekorg]

the 4001 in this configuration needs a low value resistor in series with the power connector to act as a fuse to not kill the pedal, if there is no such resistor, the diode will fail and then the whole circuit lets out the magic smoke! 100ohm is enough tho, no need to change the layout, you can just splice that resistor in line with the power wire and tape it or shrink wrap it to not short against anything, this makes it easier to replace if anything has gone wrong.

Sorry i can't really follow here. You mean 9V-100R-4001-GND in series?

Conventionally, Lug 3 faces voltage (potential difference) higher than lug 1..

Thank you i think my problem is that i can't really read schematics properly yet. In this case for me is greek. I see RV2 and 4 receive 4.5V but i have no idea how to check how much they have on the other side. I went just empirically. I don't even know if actually the lugs of the dual gang have to face the same direction or not. To me it seemed it worked properly like i did but i could be wrong. SOmetimes with other pedals i placed components in reverse and it seemed to work, but it was working in the wrong way

[iainpunk]

this is what i mean

cheers, Iain

[ghiekorg]

Thank you Iain, i modified the layout a bit but now all the components are on the board:

I have cut the ground in order to do it but in any case i  will go all around with it
I will not touch it anymore then tomorrow i will check it again. Everytime i look at it i think "i can layout it better to save some space..." but i wanna stop now

[iainpunk]

i recommend putting the 100ohm resistor in a socket so you can replace if reverse voltage kills the resistor.

cheers

[ghiekorg]

I checked it again and it seems correct... If someone wants to check it too, feel free. In the meantime i prepared the printable board


In case someone wants to build it here is the 100% scale printable A4
https://www.dropbox.com/s/utku09gavc92m98/Plague%20EQ.pdf?dl=0

[antonis]

In this case for me is greek.

So let me translate it 'cause Greek is my native language..

What actually counts for pots (wired as variable resistors in present case..) is the behavior you expect for CW/CCW shaft rotation..
RV2/RV4 should exhibit zero ohms resistance (short), between R3/R7 lower leg and RV1/RV3 wiper respectively, when turned fully CW..
(by reverse lugs 1-3 placement, the above should happen for pots fully CCW rotation..)

Here, RV2a/RV4a have no DC voltage drop across them (ideally..) due to negligible bias current and RV2b/RV4b also have no DC voltage drop due to C1/C3 blocking capacitors so what actually counts is their resistance variation in accordance with frequency/shaft rotation..
(fully CCW -> 70Hz, fully CW -> 700Hz..)

[ghiekorg]

Hi guys, today the stuff arrived and... It works! Only vol1 and 3 have to be switched
Tomorrow i will do a video, now it's night here
Thank you!

[iainpunk]

wow, really cool!
its fun to see the process of a pedal in a single thread, thanks for keeping us updated.
i love the artwork as well,

cheers, Iain

[phasetrans]

...i love the artwork as well,

cheers, Iain

I second the artwork! So crisp and strong

What is that footswitch? Does it do anything fancy like light up?

[ghiekorg]

Thank you guys. I would have never imagined that I would have made it through it haha. I owe you one
And thank you about the artwork. I think it matches our age haha
The foot switch is actually I normal switch with a mooer cap on it. I just used them to make the switch easier to press and avoid slipping. They also make my pedalboard even more colorful haha

[ghiekorg]

https://www.youtube.com/watch?v=9Gq_9dMdx5U&ab_channel=ghiekorg
here is a clip