Menatone - None More Black

bajaman · Post by **bajaman** » 21 Jul 2010, 21:25

Five DSG Jfets

J201 or possibly 2N5457/8/9

Jfet types and capacitor values or codes would be all that is required now to draw a schematic.

cheers
bajaman

Belanger88 · Post by **Belanger88** » 20 Aug 2016, 20:14

I just posted a schematic and gut shot of the 18v version which isn't the most common

Belanger88 · Post by **Belanger88** » 20 Aug 2016, 20:21

J202's are the fets actually

Belanger88 · Post by **Belanger88** » 22 Aug 2016, 02:12

Belanger88 · Post by **Belanger88** » 28 Aug 2016, 20:27

the NMB schematic has an error on it.. Jim discovered it a couple days ago when I was looking at the pics you sent and corrected it.. Was missing a 220k resistor to ground before the output buffer stage

ill post a new one asap

Intripped · Post by **Intripped** » 28 Aug 2016, 21:54

thanks,
...please post a pic with higher resolution

J0K3RX · Post by **J0K3RX** » 29 Aug 2016, 20:51

Intripped wrote:thanks,
...please post a pic with higher resolution

Try this.. Not "verified" I only traced it from the pics that Belanger88 sent me so, look it over and see if anything doesn't look right.

Big Thanks to Belanger88 for sharing your cool ass pedal! Also, for sending me the pics and getting some of the values that I couldn't see etc..

This thing is a couple pots shy of a full tone stack... easy mod

Intripped · Post by **Intripped** » 29 Aug 2016, 21:41

thanks JOK3RX!

i've checked the schematic against your drawing of the circuit-layout, and i've found two errors:
- at the input, 68k and 1M resistors are swapped (should be 68k in series with the signal and 1M to ground);
- at Q4 - the 1uF capacitor that is connected to the source goes directly to ground, there's no 1K resistor in series with it.

I'm checking against the pics now

edit:
ok, i've checked the pics also, and spotted two other errors:
- there's a ceramic cap, connected to ground, after the 68k resistor (that is in series with the signal) at the input - can't read the value;
- at Q3 - the 1uF capacitor is in parallel with the 1.8k resistor, and not connected to 220k/22n/470k as in the schematic and drawing.

edit2:
i've mede a mistake as well about the resistors at the input:
1M resistor (connected to ground) is placed BEFORE the 68k resistor (in series with the signal)

so, 1M res is the pulldown res against switching noise

J0K3RX · Post by **J0K3RX** » 29 Aug 2016, 22:43

Intripped wrote:thanks JOK3RX!

i've checked the schematic against your drawing of the circuit-layout, and i've found two errors:
- at the input, 68k and 1M resistors are swapped (should be 68k in series with the signal and 1M to ground);
- at Q4 - the 1uF capacitor that is connected to the source goes directly to ground, there's no 1K resistor in series with it.

I'm checking against the pics now

edit:
ok, i've checked the pics also, and spotted two other errors:
- there's a ceramic cap, connected to ground, after the 68k resistor (that is in series with the signal) at the input - can't read the value;
- at Q3 - the 1uF capacitor is in parallel with the 1.8k resistor, and not connected to 220k/22n/470k as in the schematic and drawing.

Ok, the 68k and 1M resistors are corrected (I blame that on copy/paste and bad eyesight)

On Q4, I believe there is a 1k8 in series with the 1u cap.. See pic attached.

You got me on the ceramic cap on the input.. I can't fully see it in any of the pics I have, I can only see that it starts with a 1.. I would say that it's pretty safe to guess that it's either 100p or less likely 10p.

Still looking at the last one you posted.

Intripped · Post by **Intripped** » 29 Aug 2016, 22:51

on Q4 the 1Uf it's in parallel with that 1.8k resistor,
it's the source resistor (from what i can see at least)

J0K3RX · Post by **J0K3RX** » 29 Aug 2016, 23:04

Here's another angle on it..

You were right on the 1u cap on Q3 source... it is in series with the 1k8 resistor.

kinda makes sense now

Intripped · Post by **Intripped** » 29 Aug 2016, 23:08

err... in PARALLEL with the resistor

J0K3RX · Post by **J0K3RX** » 30 Aug 2016, 03:38

Intripped wrote:err... in PARALLEL with the resistor

yeah, that's what I said derrr.. parallel

J0K3RX · Post by **J0K3RX** » 30 Aug 2016, 05:15

Alright.. Check it

Intripped · Post by **Intripped** » 30 Aug 2016, 08:51

looks ok to me

J0K3RX · Post by **J0K3RX** » 03 Sep 2016, 16:29

Kinda wondering about the 100k source resistor on Q5 ? Thinking something more like 10k to 22k may be a little better here?

onebuzz · Post by **onebuzz** » 01 Oct 2016, 21:53

Built one up on double sided perf using JOK3RX's schematic. Turned out very well and runs off an 18 volt wall wart. Had to use SMD adapter boards for the J202's otherwise was a pretty smooth build and it sounds the business. Thanks JOK3RX for the nice PDF schem and lay-out.

J0K3RX · Post by **J0K3RX** » 02 Oct 2016, 18:50

onebuzz wrote:Built one up on double sided perf using JOK3RX's schematic. Turned out very well and runs off an 18 volt wall wart. Had to use SMD adapter boards for the J202's otherwise was a pretty smooth build and it sounds the business. Thanks JOK3RX for the nice PDF schem and lay-out.

Nice work onebuzz! You find any mistakes on the schematic? Can you record any samples?

Honestly, I had never even heard of this pedal until Belanger88 sent me a PM and asked me if I would like to help him trace it.. Of course I said "Hell Yes!" but he answered a lot of my questions, supplied pictures and most important of all he supplied the pedal! So, the "Thanks" should go to him for sharing this cool ass pedal!

I've not built it but, if or when I ever do I will probably stick a full adjustable tone stack in it because I like to have more knobs

Belanger88 · Post by **Belanger88** » 05 Oct 2016, 12:39

does anyone have a updated working schematic for this now? also let me know if you need any info and ill take more pics and upload them so we can get it 100% accurate... then mod the balls of it

Belanger88 · Post by **Belanger88** » 05 Oct 2016, 12:45

all ceramic caps are 100pf FYI guys

Menatone - None More Black [traced]