Messages

I'll be very interested in hearing the outcome of this, as I purchased my set from the goodbuy711 as well (don't want to hijack the thread, as the problem I'm experiencing isn't exactly the same).

feel free to high-jack the thread  - you might help me figure out what I've done wrong 

Ok - have made myself an audio probe, and gone over the circuit.

I have signal up to the 3007 - guitar on pin 3 - and after the 3007 (pin 7-8) i just get a high pitched whine.

ok - R40 is definately 33r

new voltage (using regulated power supply)

jrc4558
4.5
4.5
4.5
0
4.5
4.5
4.5
9.1

tl062
*
4.5
*
0
4.5
4.5
*
9.1

mn3101
8.95
8.6
0
8.8
7.96
8.3
0.65
8.5

mn3007
8.9
8.8
3.8
8.5
0
8.6
9
9

EBC
q1   3.59  3.95  9.1
q2   3.85  4.37  9.1
q3   3.68  4.08  9.11
q4   0      0.69  0.04
q5   *      *      8.9

* = changing readings...

May I ask where you got the BBD set from...I mean, which eBay seller? Voltages are way off. The circuit is under-powered, which is most likely the cultprit.

What type of supply are you using? If it's battery, try using a new one. If it's a power supply, either it's not working properly OR somehow your 9v is turning into 7.8v. IC1 should have 9v on pin8. Also, make sure you have used a 33R on R40, and not 3k3 or 33k.

If using 2n5088, 2n5089 transistors, the pinout is CBE. Q4 should be 0v on E, but not C...which gets it's supply from Vd which is created by R40 (hence the comment above). Anyway, even accounting for the pinouts being in the wrong order there, those voltages are looking off. The emitters should have the lowest voltages, but should not be that high. I wonder if there is also a grounding issue somewhere.

When I get back, I will add in voltages for this project into the documents.

BBD set was from seller "goodbuy711" - I had a feeling it was too good to be true - but they had 100% good feedback. I'll try and get the voltages right before I hunt down another set

I was checking the voltages using a battery - but the pedal is not working with a power supply either- I will check the voltages off a regulated power supply tomorrow though - I'll check r40 again as well

pinout should actually read (i'm using 2n5088)
(EBC)
q1  4.8    5.1   7.92
q2  5.16  5.65  7.89
q3  4.91  5.2    7.9
q4  0      .689   0
q5  3.1*  3.6    7.74

[backwards]

If you don't have one, my next suggestion would be to get out the schematic, and begin to trace backwards from the output of the board along the path the effected symbol follows. You should check these things, in no particular order:

Are all the parts correct? (ie, it's easy to put a 100R resistor instead of a 100k resistor in)
Are all the parts the right way? (Backwards transistor, cap, IC, etc.)
Are all the parts installed properly? (Carefully examine your solderjoints, reflow any that look suspicious)
Are all the traces connected? (It's easy to have a broken trace ruin your day! Ignore if this is a manufactured board)

okay - traced the effected siganl back to the BBD on the schem, and as far as i can tell I have everything right. I dug out a 1uf electro and replaced the film cap in c12
I'm using a fabbed board, so the traces should be sweet

It would be good to have some voltages to confirm mine against - otherwise I'm starting to think it is my IC's that are the problem, and I'll have to get a set through smallbear. even if I have to get a new set, it would be good to confirm my voltages, so that I don't fry new chips if there is another fault...

thnaks Jacob - never used an audio probe, but now seems like a good time to learn 

i'm just wondering  - I didn't have any 1uf electros - so i used poly film caps - would this make a difference - I know usually is fine to sub film caps for electros, but this is one of the more complex pedals I've built.

Also - is there anyway I can check if my 3007/3101 are actually working? still nervous about the ebay seller....

and how do those voltages look?

Cheers

ok - voltages - any help would be greatly appreciated 

(ECB)
q1  4.8    5.1   7.92
q2  5.16  5.65  7.89
q3  4.91  5.2    7.9
q4  0      .689   0
q5  3.1*  3.6    7.74

ic1  5.9    5.9   5.9  0      5.9   5.9   5.9    7.85
ic2  *      3.93  *    0      3.9   3.9   4.01* 7.84
ic3  7.71  7.48  1.0  7.59  6.76 7.03 0.65   7.33
ic4  7.69  7.62  5.09 7.33 0      7.63 7.68   7.7


* indicates the reading was changing...

Cheers

J

Just finished my Porkbarrel. I'm getting signal on bypass, and when the pedal is engaged im getting clean signal, no chorus.  when I flick the vibe switch, i lose all signal (which makes sense as it kills the clean signal, and thats all I have at the moment),.

can anyone post voltages for me to check mine against?

Also, I bought my 3007/3101 off ebay. the seller had good feedback, but now im pretty worried they are fake.

any Ideas where I should start to debug? is a fake BBD the most likely answer here?

Cheers,

Jeremy