Fuzz and Pos Ground (again)

Started by roccster, September 17, 2014, 01:36:45 PM

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roccster

Hi all,

Im new to this forum, and to the whole DYI stompboxes. I can see why this becomes an addiction.
Im really not good at electronics, but I wan´t to learn. So I started out by ordering a BYOC, and now I am trying to figure out these layouts of pedals.
So I stumbled on Tonefiends Fuzz Face (surprise), and off course this whole thing with the Pos Ground is making me really confused (since I can´t get it to work atm).
I have searched this forum to try and find an answer that I can understand, but I guess im just to stupid. So I made this image, showing how I have wired the PCB to the box. Can a kind soul try and have a look and explain what I am doing wrong?



The issue is that the Bypass is working fine, but when I power it on it´s dead quite. So I suspect some kind of ground issue, since when I meassure the transistors I get pretty strange readings
i.e transistor 1:
E = 8.6V
B = 2V
C = 1.4V

So please have a look at the picture and tell me what Im doing wrong?
I have gone through the DIY article several times, and I just cant find it
(article url: http://tonefiend.com/wp-content/uploads/Fuzz%20Face%20Build_v02.pdf )

Hemmel

#1
EDIT : the picture doesn't show on my PC since my company's proxy blocks it.
Bââââ.

roccster


Hemmel

#3
EDIT : the picture doesn't show on my PC since my company's proxy blocks it.
Bââââ.

Kipper4

Does the battery get hot?
Note that in the pdf the led resistor goes to +9v you have it hooked up to the battery ground (-9v)
you have incorrectly labelled the jack plugs too
input jack top to bottom lugs  Ring. Tip. Sleeve.
Output  jack top to bottom Sleeve. Tip.
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

roccster

#5
Kipper,

Thanx for your input, but this is what the PDF says:
Solder the -9V (black) wire from the PCB and the -9V
(black) wire from the 9V battery snap to the other end
of the 4.7K resistor. (page 38 lover right pic)

Isn't R the inner lug (ground)
S the outer and T the one in the middle?

Sorry for getting confusing :)

Ah now I get the what you meant with the Jacks, yes the mono is marked wrong right? But IRL I have connected the wire to the tip on the Mono Jack.

roccster

Ok, updated the pic of pos. ground wiring:



Also this is the schematic, and according to this the output-jack is grounded, i just wonder to where, since the assemble PDF don´t show the output jack grounded at all?



Last night I disassembled the pedal and mounted it on a breadboard, and the first thing that I notice is just the ground problem. This was not pressent in the box, maybe the box it self grounded the output jack? Well regardless, I had a wire already attached to the ground on the output jack in the breadboard, and as soon as I grounded it (to positive ground) the bypass signal worked and the ground issue was gone. Still no signal through the PCB though.


duck_arse

as kipper says, yr diagrams show wrong. you need the wire to the right hand socket that is connected to "S" connected instead to "T" as marked it the first dia. the plug tip carries the signal, and it needs to connect to the board output. follow the blue from the board to the switch.

the rhs socket needs an earth wire, connected to the SLEEVE, no other lug but the sleeve. the other end commons with ground somewhere, right on the left hand sockets sleeve, then you know it's right. when the sockets are assembled in a metal box, the metal ferrules/flange (I dunno the correct term for it) of the sleeve, unless they are the isloated types, connect via the case. this is "a" method, but has some tricks and downfalls.

and your led needs to have the flat moulded into its case lead, which indicates K, connecting to the more (-) of your 2 wires going to it. the other side, A, goes to the more (+) wire. one of the two wires has the led resistor in series, it doesn't matter which wire it is.

oh, and I've just noticed, your left hand socket has "T" connected to the battery. T for tip always carries the signal. S for sleeve always connects to ground. R for ring sometimes is used to switch the battery on with inserted plug.
" I will say no more "

roccster

#8
duck_arse,
Thanx for getting back to me.

Ok, still not getting the drawing right (updated it again), I just looked at the pos not the letters :D

Well I have connected the left Input Jack as follows:
Ring goes to +9V on PCB and middle lug on 3DTP
Sleeve goes to Battery +
Tip goes to top left on 3DTP

And the right Output jack:
Tip to middle right on 3DTP
(no ground here)
I understand this jack needs a ground, not sure where since this is supose to be a Pos Ground wiring.

When it comes to the Led you say i dont follow... What indicates K?


soupbone

Quote from: roccster on September 18, 2014, 02:52:58 AM
Ok, updated the pic of pos. ground wiring:



Also this is the schematic, and according to this the output-jack is grounded, i just wonder to where, since the assemble PDF don´t show the output jack grounded at all?



Last night I disassembled the pedal and mounted it on a breadboard, and the first thing that I notice is just the ground problem. This was not pressent in the box, maybe the box it self grounded the output jack? Well regardless, I had a wire already attached to the ground on the output jack in the breadboard, and as soon as I grounded it (to positive ground) the bypass signal worked and the ground issue was gone. Still no signal through the PCB though.


I'm building a F.F. Clone using Dragonfly's Layout,and The "Roger Mayer Hendrix Mods",both from the layout gallery.I'm using a DpDt Switch instead of a 3pdt.(no led) The part I'm stuck at is the wiring for the d.c. jack that I installed,and the battery snap.Do you have any ideas on how this would be wired?

duck_arse

roccster - as the pedal is positive ground, and as the jack sleeves ALWAYS connect to ground, and as you have the battery positive connected to the sleeve, all the positives are grounds (put simply). easiest way is to run a wire from the right hand sockets sleeve to the left hand sockets sleeve, just there where the battery wire connects. it can't POSSIBLY be wrong then.

get your led, and have a real close squint at it. better still, look this diagram I found on the googoo's ....



in your wiring diagrams, the led resistor is connected to the black (-) lead, which is more negative than the red (+) lead (or ground for that matter). therefore, the led lead connected to the resistor in your diagrams, must be the kathode. the k must be more negative than the A for the led to light, but it still doesn't care which side the resistor is, just as long as it is there somewhere.


soup - show us a wiring diagram you're thinking of, and we can then point to the wheres and whys.
" I will say no more "

soupbone

Quote from: duck_arse on September 19, 2014, 11:08:14 AM
roccster - as the pedal is positive ground, and as the jack sleeves ALWAYS connect to ground, and as you have the battery positive connected to the sleeve, all the positives are grounds (put simply). easiest way is to run a wire from the right hand sockets sleeve to the left hand sockets sleeve, just there where the battery wire connects. it can't POSSIBLY be wrong then.

get your led, and have a real close squint at it. better still, look this diagram I found on the googoo's ....



in your wiring diagrams, the led resistor is connected to the black (-) lead, which is more negative than the red (+) lead (or ground for that matter). therefore, the led lead connected to the resistor in your diagrams, must be the kathode. the k must be more negative than the A for the led to light, but it still doesn't care which side the resistor is, just as long as it is there somewhere.


soup - show us a wiring diagram you're thinking of, and we can then point to the wheres and whys.
I'll post the link when I get up!(can't post the link from my stupid windows phone.)

soupbone

#12
Quote from: duck_arse on September 19, 2014, 11:08:14 AM
roccster - as the pedal is positive ground, and as the jack sleeves ALWAYS connect to ground, and as you have the battery positive connected to the sleeve, all the positives are grounds (put simply). easiest way is to run a wire from the right hand sockets sleeve to the left hand sockets sleeve, just there where the battery wire connects. it can't POSSIBLY be wrong then.

get your led, and have a real close squint at it. better still, look this diagram I found on the googoo's ....



in your wiring diagrams, the led resistor is connected to the black (-) lead, which is more negative than the red (+) lead (or ground for that matter). therefore, the led lead connected to the resistor in your diagrams, must be the kathode. the k must be more negative than the A for the led to light, but it still doesn't care which side the resistor is, just as long as it is there somewhere.


soup - show us a wiring diagram you're thinking of, and we can then point to the wheres and whys.
Sorry it took so long to get back with you.I have A.D.D.(Attention Dave Disorder.lol) So,Here's the layout i'm using; http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album18/album151/DALLAS_ARBITER_FUZZ_FACE_SILICON_PERF.gif.html    and the "Hendrix Mods"; http://www.aronnelson.com/gallery/main.php/v/Richard-Boop-RLBJR65/album84/FFace.gif.html  There's the layouts.I am doing it on perfboard this time.I'm using AC128 Germanium Transistors(PNP Build),a Carling DpDt Switch,and d.c. jack plug like this; https://www.smallbearelec.com/catalog/DCjack.jpg

roccster

Sweet, thanx m8!

I mannaged to get the JB Fuzz Face to work just fine. Just switched the pos and neg from the battery connector. Problem was in the polarity of the trannies. After I sorted them out everything worked ok. Not thrilled with the sound of the JB though, think it´s way to muddy for my taste so my search for a fuzz continues :)

Cheers!

duck_arse

#14
wire the dc jack to suit the plug attached to the supply/wall wart/adaptor. so if your supply plug has centre negative, the only way to wire the jack is as shown. you still switch the positive lead, whether positive ground or negative. .... I might be wrong ....



this one, being dragonfly's layout

:icon_redface: shows "BC108 or similar PNP silicon" which is 100% incorrect, as   :icon_redface: the bc108 is an npn type. AND they are shown backwards for the bc5xx, the flats face the other direction if you want the bc series collector to supply. the bc108 comes in a metal can with emitter tab. oh, well. I think the electros are backwards for pos ground as well, but the parts positions might be alright ......

and this one showing the circuit


seems correct (except for the millenium switch line polarity). collect up all your grounds on the pcb and run one wire to the dc jack "to board +" lug, and one wire to the sleeves, cause they are always ground, and one wire from the centre pin back to "-9V". and don't daisy-chain the supply with a neg ground pedal, or you'll short the supply and both pedals stop.

the best thing you can do is draw the whole circuit (NOT the layout, the circuit) and include all the stuff, bypass switch, dc jack, battery, all. when you have the circuit CORRECT, the wiring is a doddle. let the mechanical follow the electrical, not the other way round. I hope this helps.


[edit :]  :icon_redface: oopps, don't know how many times I looked at that circuit and the datasheet. I knew something was wrong, but still managed to stuff it up. the diagram says npn, I read pnp. the rest of the post is, at least until further notice, correct.  :icon_redface:
" I will say no more "

soupbone

Quote from: duck_arse on October 31, 2014, 10:17:36 AM
wire the dc jack to suit the plug attached to the supply/wall wart/adaptor. so if your supply plug has centre negative, the only way to wire the jack is as shown. you still switch the positive lead, whether positive ground or negative. .... I might be wrong ....



this one, being dragonfly's layout

shows "BC108 or similar PNP silicon" which is 100% incorrect, as the bc108 is an npn type. AND they are shown backwards for the bc5xx, the flats face the other direction if you want the bc series collector to supply. the bc108 comes in a metal can with emitter tab. oh, well. I think the electros are backwards for pos ground as well, but the parts positions might be alright ......

and this one showing the circuit


seems correct (except for the millenium switch line polarity). collect up all your grounds on the pcb and run one wire to the dc jack "to board +" lug, and one wire to the sleeves, cause they are always ground, and one wire from the centre pin back to "-9V". and don't daisy-chain the supply with a neg ground pedal, or you'll short the supply and both pedals stop.

the best thing you can do is draw the whole circuit (NOT the layout, the circuit) and include all the stuff, bypass switch, dc jack, battery, all. when you have the circuit CORRECT, the wiring is a doddle. let the mechanical follow the electrical, not the other way round. I hope this helps.
Thanks!