Bazz Fuzz - No Sound - Debug

[mow]

Hi,

I just joined the forum and first of all want to say hello to all of you!


Today i built the Bazz Fuzz after the schematic of Fuzz Dog (former poodlespedalparts) on perfboard.
I use the MPSA13 and thus a 10K resistor instead of a 100K.

I soldered everything in place, but it just doesnt seem to work! No sound at all!
I tried to debug it myself and tested alot: Everythings wired to ground, batterys full, connections seem solid, wired everything after the schematic, swapped the transistor, swapped a resistor, took the voltage (after the first resistor (not CLR for LED), i got ~1,25 V. After both capacitors the voltage is at zero, before, ~1,25V. I used WiMA film caps.

Im absolutely desperate 

I built 2 easy kits before, which worked perfectly in the first place.
This is my first build on vero.
I´ve got pics, i just dont know how to upload them?
I hope you can help me solve this mystery


Greetings mow

[Elijah-Baley]

I use to upload the image on imngur and use the url web link to insert in the post.

Anyway, the circui is very simple, check the orientation of diode (or led) and transistor, and polarized caps (if you used them).
Are you soldered the footwsitch already?

I'm testing a bazz fuss now. Gound and negative battery go to the sleeve of the jack output. Check the wiring.

[mow]

Hi,


No, I haven´t soldered the footswitch yet, wanted to test the board before.
I used film caps, thus non polarized. The transistor should be correct, collector is, where the signal goes first right? And the black stripe on the diode indicates that thats the negative side, right? If that´s the case then it should be correct.
I´ll upload pics tomorrow, its pretty late already where I live.

Greets
mow

[mow]

Hi,

here are some pictures of my build:

Bazz-fuzz-3.jpg



Bazz-fuzz-2.jpg


Please excuse the ugly soldering, it looked nicer, before i tried to debug it

Greets
Mow

[duck_arse]

erm, I went to look at the pics, couldn't get past all the downloads and ads and popups. is there any way you can post the address of the image between the tags the button provides? it's always much nicer to see the pics in the thread, rather than chasing across the big bad webs trying to find.

and hello. the bazz is so simple, it will be working sooon.

[mow]

I´m very sorry, but I tried to embedd it in the post but it didn´t work, so i switched it.
But the links should be fine, i hope?

Yes, the Bazz Fuss is about as simple as it gets, and I think the problem is right infront of my eyes! But I cant seem to find it, searched for hours!

*edit* I try to find another host to post the pics!




Greets
Mow

[Elijah-Baley]

Could you link us the schematic? I'm seeing two resistor, my layout has just one!
I've some difficults to read the circuit.

Do you have some stripboard? That could be clean, as work.

[mow]

Here´s the schematic that i use:

One of the reistors is a 2k2. A current limiting resistor for the LED.

http://pedalparts.co.uk/docs/BazzFuzz.pdf

I used it, because my first two pedal kits were ordered there, and everything worked fine.

Greets
Mow

[disto]

Hi Mow,

What transistor are you using the 2n5088, the PDF mentions a number of alternatives? Have you checked the transistor legs? In an earlier post you said the signal goes into the collector but I think it should go to the base first. For the 2n5088 the legs go Collector, Base, Emiter. So C1 and the cathode of D1 should connect to the middle pin (the collector) of the transistor.

As Elijah-Baley says, I would recommend stripboard over padboard. It will be a bit cleaner and you wont have to use so much solder.

Don't give up, keep trying... The Bazz fuzz is a nice little project.

[Elijah-Baley]

I use the MPSA13 and thus a 10K resistor instead of a 100K.

I believe same "feet" of the 2N5088. I tried both.

[mow]

The pins of the MPSA13 are E B C, when the flat side is facing you.

I just tried it out, but still nothing happened.
Then i again checked the schematic, and it should be right the way i soldered it.(so leg connection should be good)

Absolutely unbelievable how annoying such a small fuzz can be! 

I think tommorow I´ll just start over again and see how that goes...
But I still really want to know where the problem is at!


Greets

[Kipper4]

Have you checked all your nodes for continuaty with a DMM?
Have you made an audio probe? If not why not?
The audio probe may just find your problem faster than a meter.
Have you gone over the back of the perfboard with a craft knife to make sure theres no shorts between the pads. It looks like theres some solder spatter.
I'm still not sure which jelly bean you used?
I'm sure we can all help to narrow it down.
Welcome to the forum mate.

[disto]

Its a bit hard to tell if the multiplier is red or orange but it looks like R1 might be a 100K.

If its is a 10K and you have a spare mono socket. You could try building an audio probe. There's a bit about how to build one here http://www.diystompboxes.com/pedals/debug.html. See what you can hear after C1, after C2 and at the output.

[mow]

Just checked the nodes with my DMM.
Everythings alright. 9V in the beginning, after the 10K resistor voltage is 1,25 everywhere. No voltage after caps.

No, I haven´t made an audio probe yet, but it´s on my To-do list.

I´ve checked everything for unwanted solder bridges the fifth time by now, no solder bridges (I hope! )

I built it exactly like the BOM and schematic of fuzzdog says, except i use a MPSA13 and a 10K instead of a 100K.


Greets

[mow]

I just made a non permanent audio probe, and tested the circuit.

I just dont know what to look for really?


I get a fuzz when i touch the big solder cross in the middle or the the red wire solder spot that goes to the pot.

The rest is just crackling.


Greets

[Kipper4]

So you get 1.25v after a 10k resistor attached to a 9v battery?
Stick the DMM on ohms setting and check that 10k (power off to the circuit)
Somethings wrong there I think.
Even if you stick a 100k between the battery terminals I get less than 1/2V in power loss.
I could be wrong. I'm sure some one will say if  am.

[Kipper4]

Hook the guitar up to the input jack.
hook probes jack to your amp input and dont forget to ground the probe to the effects ground. I have an alligator clip on mine.
probe the node between the wire coming from the input jack tip and C1 (220nf)
probe the diodes cathode- (striped negative side of diode) and C1
probe the node R1  C2   D1 (anode+ side)
this is essentially your signal path from guitar through the circuit upto the fuzz pot.

[mow]

Tested the resistor: perfect 10k

If I audio probe EVERY solder joint, i get fuzz on the big solder cross and crackling everyhere else.
Should i get fuzz everywhere?

Greets

[Kipper4]

do you get fuzz on lug 3 of the pot?

[Tony Forestiere]

The input jack is a TRS jack used for battery switching. As you have the battery -9 tied to ground at the output jack and the board ground, the battery SHOULD be on, (just won't switch the battery off when you unplug the input jack).
Re-check the in from the board and make sure it is not connected to the "Ring" lug.
Just a SWAG.