BJFE - Emerald Green Distortion Machine  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.

Re: BJFE - Emerald Green Distortion Machine

Postby roseblood11 » 24 Jun 2015, 21:00

Could be anything rated for 2 ampere, 1200 volt, maybe STTH212



I think the schematic was posted somewhere, but I can't find the link anymore...


Has anybody tried this pedal with a Proco Rat in front of it? A real Vox set to light crunch sounds great if its boosted with a rat. Could be interesting to put both circuits in one enclosure.
roseblood11
Tube Twister
 
Posts: 1803
Joined: 23 Aug 2008, 15:21
Has thanked: 347 times
Have thanks: 309 times

Re: BJFE - Emerald Green Distortion Machine

Postby roseblood11 » 24 Jun 2015, 21:08

@ the3secondrule: Could you measure the hfe of all transistors and the leakage of the 2n1309? That would be helpful to understand the biasing...
roseblood11
Tube Twister
 
Posts: 1803
Joined: 23 Aug 2008, 15:21
Has thanked: 347 times
Have thanks: 309 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 26 Jun 2015, 22:22

BJF wrote:Hi,

Here you go:
http://tagboardeffects.blogspot.se/sear ... l/BJF%2FMP

And no I don't mind and never did if anyone wants to build one for their own use or a friend.

Fun note perhaps is that when doing the Bearfoot version some nice 2N1309 had been scouted for another model and I could not resist to try and liked that.
Original BJF model has same circuit but all were made with silicon metal cans medium gain drivers.

have fun
BJ
BJF Electronics


I drew separately the schematic in accord with the strip board layout.

emraldschematic.jpg
You do not have the required permissions to view the files attached to this post.

For this message the author Manfred has received thanks: 5
atreidesheir (28 Jun 2015, 05:09), HENK (27 Jun 2015, 05:11), modman (10 Jul 2015, 12:28), ppluis0 (04 Jul 2015, 01:40), roseblood11 (27 Jun 2015, 15:16)
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby soulsonic » 26 Jun 2015, 22:43

roseblood11 wrote:@ the3secondrule: Could you measure the hfe of all transistors and the leakage of the 2n1309? That would be helpful to understand the biasing...

The 2N1309 in mine had "329" marked on the side. I assume this is the Hfe.

For this message the author soulsonic has received thanks: 3
HENK (28 Jun 2015, 05:29), Manfred (27 Jun 2015, 19:56), roseblood11 (27 Jun 2015, 15:16)
User avatar
soulsonic
Old Solderhand
 
Posts: 3530
Joined: 27 Jun 2007, 04:38
Location: Buffalo, NY
Has thanked: 56 times
Have thanks: 269 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 27 Jun 2015, 08:09

I'm sorry but I made a mistake on the schematic, the FET types are 2N5952.

For this message the author Manfred has received thanks: 3
HENK (28 Jun 2015, 05:30), modman (10 Jul 2015, 12:29), roseblood11 (27 Jun 2015, 15:16)
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 28 Jun 2015, 18:43

I took closer look at the PLC shot,
and found a resistor value of 470kOhms on the gate of the second FET.

By the way, the FET stages are alike in the circutry of the Baby Pink Booster,
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 01 Jul 2015, 11:34

Better readable now.

Emerald.jpg
You do not have the required permissions to view the files attached to this post.

For this message the author Manfred has received thanks: 4
deltafred (01 Jul 2015, 15:36), HENK (01 Jul 2015, 15:11), modman (10 Jul 2015, 12:29), soulsonic (01 Jul 2015, 20:20)
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 01 Jul 2015, 20:36

The LED circuitry is the same as with other BJFE pedals.

EmeraldLEDsupply.jpg
You do not have the required permissions to view the files attached to this post.
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby deep_intruder » 02 Jul 2015, 13:39

In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!

For this message the author deep_intruder has received thanks:
Manfred (02 Jul 2015, 19:46)
deep_intruder
 
Posts: 3
Joined: 28 Apr 2012, 20:05
Has thanked: 11 times
Have thanks: 2 times

Re: BJFE - Emerald Green Distortion Machine

Postby smanq » 02 Jul 2015, 16:41

deep_intruder wrote:In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!

I think the 4n7 cap is right connected to the source (like on other BJF circuits), but the 1uf cap (the circuit output) must be connected to the drain.
smanq
 
Posts: 14
Joined: 05 Sep 2007, 15:47
Has thanked: 0 time
Have thanks: 2 times

Re: BJFE - Emerald Green Distortion Machine

Postby deep_intruder » 02 Jul 2015, 17:38

smanq wrote:
deep_intruder wrote:In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!

I think the 4n7 cap is right connected to the source (like on other BJF circuits), but the 1uf cap (the circuit output) must be connected to the drain.


I do not know how is the original, but the layout from tagboardeffects.blogspot.se is as I said.
deep_intruder
 
Posts: 3
Joined: 28 Apr 2012, 20:05
Has thanked: 11 times
Have thanks: 2 times

Re: BJFE - Emerald Green Distortion Machine

Postby Frank_NH » 02 Jul 2015, 19:34

deep_intruder wrote:
smanq wrote:
deep_intruder wrote:In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!

I think the 4n7 cap is right connected to the source (like on other BJF circuits), but the 1uf cap (the circuit output) must be connected to the drain.


I do not know how is the original, but the layout from tagboardeffects.blogspot.se is as I said.


I've been following this thread and deep_intruder is correct. The vero layout has the 4.7 nF cap connected to the drain. There is already a 22 uF source resistor bypass cap at the last JFET, so I don't know if connecting the 4.7 nF cap also to the JFET source would do anything. Hence, it's probably correct going to drain, but perhaps someone could confirm that.
Frank_NH
Breadboard Brother
 
Posts: 132
Joined: 12 Jun 2013, 15:18
Has thanked: 17 times
Have thanks: 66 times

Re: BJFE - Emerald Green Distortion Machine  [traced]

Postby Manfred » 02 Jul 2015, 19:58

deep_intruder wrote:In my opinion there are two mistakes, the two caps: 1u and the 4n7 of the last fet, both must be wired to the drain and not to the source!

You are right, thanks for pointing out the mistake.
My bad. The stripboard layout is all right.

Here the corrected schematic:

EmeraldCorrected.jpg
You do not have the required permissions to view the files attached to this post.

For this message the author Manfred has received thanks: 2
Frank_NH (03 Jul 2015, 13:09), HENK (03 Jul 2015, 04:26)
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby smanq » 03 Jul 2015, 08:27

OK, the schematics reflect the board layout.
But if the A50K pot controls trebles, I confirm what I said before.
If we connect the 4n7 cap to source, when the wipe is full CW, both first and last stages have a boost on high frequencies (exactly a low cut on first stage); when the pot is full CCW last stage is around linear (4n7 has no effect on circuit) and first stage has a boost on low frequencies. It's same behavior we can see in other BJF circuits, like honey bee. So, in this way: CW=treble boost, CCW=bass boost.
If we connect the 4n7 cap to drain, when the pot is full CW we have a treble cut on last stage and a low frequencies cut on first stage (around a non sense); when the pot is full CCW last stage is around linear, the first stage has a boost on lows. This behavior for me is strange: CW=treble cut, CCW=bass boost.
smanq
 
Posts: 14
Joined: 05 Sep 2007, 15:47
Has thanked: 0 time
Have thanks: 2 times

Re: BJFE - Emerald Green Distortion Machine

Postby Manfred » 03 Jul 2015, 21:05

smanq wrote:OK, the schematics reflect the board layout.
But if the A50K pot controls trebles, I confirm what I said before.
If we connect the 4n7 cap to source, when the wipe is full CW, both first and last stages have a boost on high frequencies (exactly a low cut on first stage); when the pot is full CCW last stage is around linear (4n7 has no effect on circuit) and first stage has a boost on low frequencies. It's same behavior we can see in other BJF circuits, like honey bee. So, in this way: CW=treble boost, CCW=bass boost.
If we connect the 4n7 cap to drain, when the pot is full CW we have a treble cut on last stage and a low frequencies cut on first stage (around a non sense); when the pot is full CCW last stage is around linear, the first stage has a boost on lows. This behavior for me is strange: CW=treble cut, CCW=bass boost.


Your explanation makes sense because there is already a treble control.
It is hard to find out the real circuitry on the pcb shots.
Is there an owner of this device who could check it out which the real circuit is?

EmeraldTwoVersions.jpg
You do not have the required permissions to view the files attached to this post.
Manfred
Cap Cooler
 
Posts: 673
Joined: 05 Apr 2009, 00:42
Has thanked: 960 times
Have thanks: 505 times

Re: BJFE - Emerald Green Distortion Machine

Postby IvIark » 10 Jul 2015, 14:03

Hi guys. The schematic was sent to me a while ago and I think at the time I was asked not to share it, but can't completely remember so here it is. If the author would prefer me not to then please let me know and i'll remove it from here.

It doesn't flow like many of us may be used to seeing schematics for these things and as such the scheme isn't as straight forward to follow at first. Q1 has the source at the top and drain at the bottom

Bearfoot-EGDM-rev2.png
You do not have the required permissions to view the files attached to this post.
"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

For this message the author IvIark has received thanks: 5
deltafred (10 Jul 2015, 18:37), HENK (11 Jul 2015, 15:01), Manfred (10 Jul 2015, 17:50), modman (10 Jul 2015, 16:11), nickthemen (10 Jul 2015, 21:28)
User avatar
IvIark
Tube Twister
 
Posts: 2297
Joined: 02 Jan 2008, 00:59
Location: Manchester UK
Has thanked: 667 times
Have thanks: 676 times

Re: BJFE - Emerald Green Distortion Machine

Postby modman » 10 Jul 2015, 16:22

Manfred top drawing conforms to this schematic made in 2014...look at the 4nF cap marked as
However, have a look at C14 in the old one: there is written "100k = 10pF", other schematic has this value as 100pF, don't know where that came from.
Maybe the solution the capacitor has 100k written on it, meaning 100,000 (pF) = 100nF?
C15 = 22nF or 22µF? - if you have the unit in front of you, how could you have to guess? Maybe it was traced from pictures, not from a unit.
You do not have the required permissions to view the files attached to this post.
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)
User avatar
modman
a d m i n
 
Posts: 4301
Joined: 19 Jun 2007, 17:57
Has thanked: 3108 times
Have thanks: 546 times

Re: BJFE - Emerald Green Distortion Machine

Postby asimplesample » 24 Oct 2016, 01:38

I just ran across this effect today, and found this thread and the 'tagboard' layout. This thread ends with some doubts...has anyone made a final confirmation? Has anyone built one all-silicon?
Thanks!
Larry S.
asimplesample
 
Posts: 12
Joined: 29 Jul 2009, 18:16
Has thanked: 6 times
Have thanks: 11 times

Re: BJFE - Emerald Green Distortion Machine

Postby BJF » 25 Oct 2016, 15:00

Hi There,

Oh that schematic doesn't flow well at all.
Really it's a straight forward design and as I wrote several years ago that if you'd take a BJF EGDM apart you would find three transistors

Indeed BJF version is all silicon while when I was making this for Bearfoot and seeing they had 2N1308's in stock I just went for it and really liked the sound and that is precisely what happened.

At your service
BJ

For this message the author BJF has received thanks:
J0K3RX (25 Oct 2016, 18:57)
User avatar
BJF
Resistor Ronker
 
Posts: 269
Joined: 03 Nov 2007, 11:37
Has thanked: 2 times
Have thanks: 54 times

Re: BJFE - Emerald Green Distortion Machine

Postby Seiche » 27 Apr 2018, 05:39

Manfred, the top one should be correct.

I'm working on it to verify.

For this message the author Seiche has received thanks: 2
Manfred (27 Apr 2018, 14:59), Nocentelli (27 Apr 2018, 07:21)
User avatar
Seiche
Tube Twister
 
Posts: 2477
Joined: 01 Nov 2010, 01:16
Location: Germany
Has thanked: 241 times
Have thanks: 181 times

PreviousNext

Return to Boutique Stompboxes dissected...

Who is online

Users browsing this forum: No registered users and 2 guests