fuzz face problems

[cove]

:? i just finished  a fuzz face from general guitar gadgets...used good part and matching transitors. it works but, when i turn the fuzz control all the way up the whole pedal "cuts out"

ive checked the wiring and it seems okay...i used the resisotrs values that came wiht the matching tranistors from Little Bear Electornics..

how dirty should this effect be?

any ideas to save this project or should it cut out?  any advice on guitar , amp or settings for a good sound?

Thanks

[Roland]

Check the fuzz pot (1K) and or the electrolytic cap for proper polarity. It sounds like a bad or dirty pot, try replacing  it.

[petemoore]

take battery voltage.
 Then take the 6 transistor pin voltage readings from ground.
 Post themhere.
 The pot should work in the circuit throughout it's range...something funy there...how fuzzy does it get before cutting out?

[cove]

Q1 voltages are as follows

collector .1v
base 8.9 v
emitter 9.1 v

Q2

collector .1 v
base .5 v
emitter 9.1v

battery 9.5 v

this is a negative ground version  http://www.generalguitargadgets.com/v2/diagrams/fuzzface_lo_pn3.gif

thank

[smoguzbenjamin]

Are you sure you got the pinouts right? 8.9v at a transistor's base looks weird in any acse but it seems like you've swapped the collector and emitter around on both trannies... could I be right?

[cove]

iam using transistor sockets and the emitter is the one with the bump out of the socket base and
the one next to it is the base and the next the collector..and only one orientation for the placement of the transistors in the socket so i think its okay but i do have 8.9 volts at the base and 9.1 at the emmitter...i really thank you for the help

[smoguzbenjamin]

Do remember that not all transistors have the same pinout. Are you 300% sure you are putting the right pins in the right socket holes?

[petemoore]

FF: Q1 emitter to ground [or not], always a good one to look at.
 USe DMM Beep mode, ...ground would b e the smooth battery clip terminal, the one that the pole of the pattery with the - sign next to it goes to.
 In an NPN neg ground version of  a FF this should connect to a lug of each pot and the Q1's emitter...making sure you're getting good beeps from all those points to one of those points is a good one to do...while you're at it if you like...check to see that ground is'tn going somewhere it shouldn't.
 I st sus a miswire or mis orientation in there.
 I didn't see whether it's been indicated what type transistors or whether this is a NEG or POS ground project.

[cove]

these are the latest voltages checked and rechecked.
Q1 voltages are as follows

collector .1v
base 8.9 v
emitter 9.1 v

Q2

collector .1 v
base .1 v
emitter 9.1v

battery 9.5 v
i sure of the transistor orientation i only have a digital multimeter for measuring voltages and ohm
this is a negative ground project and the parts layout link is posted
does it look like the base of Q1 is off and maybe the emitter of Q2?

thanks

[brett]

The base-emitter difference should be 0.6V for Si and 0.3V for Ge tyransistors, so your voltages on Q2 are definately not right (but Q1 is probably ok).  Hope that helps somehow.

[cove]

checked everything again and got

Q1
e-9.1v which is right to the v+
b-9.04 v
c- 8.65v

Q2
e 8.65v
b-8.55v
c-2.2v

does this sound okay

[petemoore]

Backwards to me.
 Ie the collector is way 'lower'...
 if you actually state what type [pos ground / neg ground] circuit or the actual name of the circuit, or post a link to the circuit ?
 Then I would start with your transistor pinouts

[cove]

sorry for any confusion there were no negative values here are the correct ones
Q1
e 9.1v which is right to the v+
b 9.04 v
c  8.65v

Q2
e 8.65v
b 8.55v
c 2.2v

iam using this project
http://www.generalguitargadgets.com/v2/diagrams/fuzzface_lo_pn3.gif
and its negative ground
the project seems to work but might be to dirty sounding, i just need to know do i have
to still correct something or am i okay .

thx

[petemoore]

And I do unless I missed something.
 That diagram won't work.
 We tried and tried a few times.
 It is a trap...maybe someone knows how to make it go.
 Pick a PNP POS ground schematic.
 All you really have to do is use film caps for input output, put the 22uf so it's + to ground, use PNP transistors with their Emitters toward ground, connect battery + to ground - to where the battery connect at the 'top' of the schematic.
 Ditch that schem...it keeps trapping FF builders...it won't work, even with all the kings horses and men, unless Humpdy missed somwthing...
 Just find a tried true basket for your eggs...PNP POS ground or NPN neg Ground.

[cove]

thanks so much for your help on the forums...attached is link to the pos grnd FF . can i change the neg grnd to pos ground and leave out the dc power jack and make this work.
any suggestions you have to still use the pcb and parts to make it work would be helpful

pos grn : http://www.generalguitargadgets.com/v2/diagrams/fuzzface_lo_pp2.gif
neg grn: http://www.generalguitargadgets.com/v2/diagrams/fuzzface_lo_pn3.gif

thanks again
bruce

[petemoore]

http://www.generalguitargadgets.com/v2/diagrams/fuzzface_sc_pp.gif
 Sorry I'm not that good at reading those layout ones like that.
 But both those look to me I ddunno
 One says NEG Ground [the bottom link you provided] and sure looks to me like the Batt Pos Is going to ground...[even tho it looks kinda OK..I never tried it and forget which ones are the 'unsolved troublemaker']
 The one shown here should be just fine for PNP transistors ... Is THAT Waht you HaVe? PNP?
 the only things you have to look for [only lol] to convert to POS ground PNP version [which I know works as shown] is...Batt pos to ground [bottom of the schematicunder Q2,   Q1's emitter,    and vol pot]
 The batt NEG Goes to the 33k and [what/// 470 ohm or] 1k resistors above Q1 [at the top of the schem.
 You Always want the polarized caps in the 'right way' which is following where the most positive and negative connections are and matching those to the polarity marking [-] on the cap...in this case since the polar cap Is connected to batt pos [POS Ground version] the positive side [opposite the - marking] of the cap goes to POS / ground.
 The other caps I think are marked also...if you use films they 'work both ways' and so there is no polarity on them...thereby removeing polarity issues...just follow where it says + on  the schematic to use polarized caps there.
 Of course the emitter faces the 'bottom' of the board and the schematic...collector toward the 'top'.
 Let me know how it's going !!!

[petemoore]

Unless you have really well filtered power from AC sounce, a DC jack on a FF is going to provide noisey operation compared to a battery.
 You might want to try it first and see if you can live with it, then get rid of it.
 The FF is designed also to have a battery's internal resistance there as part of the circuit and may not be the same using a filtered AC source...I never messed with it.
  Yes you can use a DC supply, however thismust be separate from any NEG ground efkts [that's why the schematic had DC JAck on it...if you figure that one out let me know]...also...
  I wouldn't recommend it [DC jack on FF] with the schematic I suggested, [or anyway].

[toneman]

mayb i can help.
like the man said, i'd love 2 help U out,
which way did U come in?

a quick lookover the layout and schemo U linked 2
seems like the layout is corect.
What's *really* confusing is the "PNP, Negatve Groound"
notation on the pcblayout.
Where the schematic has the triangle gnd thingie, call that
9Vneg.  this is "actually" a POSgnd circuit since it uses
PNP trannys.  the "gnd" symbol is technically in wrong place,
since 9Vpos is the "return" or "common" of the circuit.

So, R2&R4 join 2gether @ 9Vneg.
Q1-E Bottom of R6 & PlusSide of C2 go 2 9Vpos.
Bottom of R10 goes 2 9Vneg.
The "common" of J1 and J2 should goto 9Vpos.
Schematic wrongly indicates(with gndthingie) 9Vneg.
With neg lead of voltmeter at POS side of batt, U should
have 0V at in/out jack's "gnd" (case) connector.
If U have 9Vneg....oops....wrong polarity!!
Still, with neg lead of meter at 9Vpos, junction of R2&R4
should B @ 9Vneg.  this is most neg of circuit.
The layout is correct.  The "gounding" is caddywompus.
Also, make *sure* U have E, B & C correct.
Sometimes it's E, C & B...
may U fuzz like U never fuzzed B4!
tone

[cove]

Everyone thanks for your help ...what i finally did was to make the FF a pos ground
project by switching around  a few components and wires...WOW...it works.

Bruce

[petemoore]

Pretty amazing what just two transistors can do in a FF...!!!