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Thx for the advice, but the one that is working is the oldest, this is the youngest that ain't working ! (My grand father could have said this  )

Hello again,

So, here is what I've tried so far :

• replace Q5 with another 2n5088 -> still no variable voltage on Collector pin.
• replace all the transistors with 2n3904 (suspecting out of specs 2n5088 from cheap chinese seller) : same 7V on Q5 collector pin
• check if there wasn't an inversion between R41 and R37 : they are at the right place.
• check R38 : correct.
• Test MN3101 et MN3007 in another working Pork Barrel (an ooold one from 2011) : working fine
• Check voltage without MN3101 suspecting a faulty socket : 0v on Pin 6 so socket seems to be fine.
• resolder every joint that I found a little off.

Well, still not working...

What do you think can cause Pin 6 of clock and collector pin of Q5 to have fixed voltages ?

Thank again.





I've swap

Thank you for your suggestions danfrank.
I've tried to bias the pedal, but as I didn't hear any effects I left the trimmer in his middle position.
I've tried with a regulated 12v power supply and still no chorus, just a weak effect, even when biasing.
At first I thought that it was one of the 2015 pcb that had to have some corrections as you mention, but mine it's the rev. 1 that has been already corrected.

Hello everybody,

Because of the pandemic my employer puts me on hold until better days so I've got plenty of times and decided to try to get back at building pedals.
I've been succesful with a Tractor Beam and a Decimator clone (really effective noise gate btw).
So, following that path, I was confident in trying a Pork Barrel 2015 rev.1 that was sitting in my drawer next to a couple of MN3007 and MN3101 that I've traded with a fellow madbeanforum user some years ago.

Everything went well while soldering, but once I fired it up : fail !

I can hear a tiny change of sound when I engage the effect, like the Depth is kind of working, but oscillations are very weak and almost inaudible, it's almost a dry signal.
The LFO Led is blinking so I'm guessing the LFO is working though.
I've double check my soldering and resolder some joint, but still the same.

So I've made some measures and notice that Pin 6 on clock is way off, so is collector on Q5 (and maybe emitter on Q3)

If you guys have some time, could you please point me in the right direction to debug this one ?

Thx

IC1 : 4558
----------
1 | 4,72
2 | 4,72
3 | 4,72
4 | 0
5 | 4,72
6 | 4,72
7 | 4,72
8 | 9,1

IC2 : MN3007
-------------
1 | 9
2 | 4,64
3 | 3,9
4 | 0,6
5 | 0
6 | 4,6
7 | 3,73
8 | 3,73

IC3 : MN3101
-------------
1 | 8,98
2 | 4,6
3 | 0
4 | 4,68
5 | varies
6 | 8,05*
7 | varies
8 | 0,6

IC4 : TL062
-----------
1 | varies
2 | 4,56
3 | varies
4 | 0
5 | 4,55
6 | 4,57
7 | varies
8 | 9,1

Q1 : 2N5088
-----------
E | 3,55
B | 4,05
C | 9,1

Q2 : 2N5088
-----------
E | 3,96
B | 4,51
C | 9,1

Q3 : 2N5088
-----------
E | 3,72*
B | 4,2
C | 9,1

Q4 : 2N5088
-----------
E | varies
B | varies
C | 9

Q5 : 2N5088
-----------
E | 0
B | varies
C | 7,7*

here are some pics of the PCB

Hello Brian and thx fo the answer.

I've checked the trimmers, I've got a 20k for Bias, a 10k for Cancel, and a 1M for Clock.
I've removed the MN3005 and mesure the voltages, remelt the joints and mesure again and it is still twice what it should be.
I've totaly remove the socket and mesure directly on the board, same voltages.
I've removed R20 and R21 and put on new ones, still twice the voltages...
I also change the Cancel Trimmer, no luck too. (I've got 8,47v on the three legs of the trimmer, don't know if it's normal though).

Maybe be I fryed the PCB somehow...

Well, hello again, and back on this one today with no luck again.

Here is where I am :

I've got audio signal on pin3 of IC3, but very distorted.
The sweet spot to get this weak distorted signal is about half the Bias pot (though it says 1/4 to 1/6 in the doc).
When I try the pedal, i've got no delays but a kind of self oscilation that becomes a sort of slapback in the first 1/8 of the delay pot., then nothing passed that point.

Here are the voltages I've got at 6,5 kHz and 8,58V power supply (* are the voltage that I found different from the build doc).

IC1 : 4558D
--------------
PIN 1 : 4,29
PIN 2 : 4,29
PIN 3 : 4,29
PIN 4 : 0
PIN 5 : 4,29
PIN 6 : 4,29
PIN 7 : 4,29
PIN 8 : 8,58

IC2 : V571D
--------------
PIN 1 : 1,3
PIN 2 : 1,85
PIN 3 : 1,85
PIN 4 : 0
PIN 5 : 1,85
PIN 6 : 1,85
PIN 7 : 2,9
PIN 8 : 1,85
PIN 9 : 1,85
PIN 10 : 3,05
PIN 11 : 3,05
PIN 12 : 1,85
PIN 13 : 8,58
PIN 14 : 1,85
PIN 15 : 1,85
PIN 16 : 1,07

IC3 : Xvive MN3005
----------------------
PIN 1 : 8,55
PIN 2 : 3,99
*PIN 3 : 8
*PIN 4 : 7,96
PIN 5 : 0
PIN 6 : 3,99
PIN 7 : 4,3
PIN 8 : 0,54

IC4 : MN3101
----------------
PIN 1 : 7,95
PIN 2 : 3,99
PIN 3 : 0
PIN 4 : 3,99
PIN 5 : 3,97
PIN 6 : 3,9
PIN 7 : 3,9
PIN 8 : 0,53

The only change I've made from the BOM is a V571D in place of a NE570.

I'm attaching some pics of the board too, maybe you'll see something I've missed.

If you guys have some time to help me with this one, that'll be awesome.

Thx

Hello all,

After almost a year away from the workbench, I'm back with an aquaboy.

Everything went well so far, voltages were consistent with the build doc and I've got sound and delays.
Freq . is 6.6Hz and the pedals is running at 9V.
But since I started to calibrate with audio probing, delays are now weak and distorted, Pin3 and 4 of the Mn3005 are at 8.40V and Pin7 is 5.3V.

If I audio probe on pin7, I've got a clean sound.

Is it possible that I've fried the mn3005 Chip while calibrating ?

Thank

I've just ordered one with shipping to France.
I was only charged $2.50 for shipping.

Another VFE project. As always, this a very versatile pedal. I use it in front of the amp as a mild overdrive and it sounds nice.

I will source another one and let you know if it resolves the issue.
Thanks again for your help.

Well If I remove the Mn3008, pin 13 is at 7,5V.

So I'm guessing I've got a faulty Mn3008.
I've sourced it at banzai music in Germany, where I've purchased several mn3007 before, so I was confident.

So, I've checked for R14, R17 and R16, they have the right values.
Since I'm colorblind I had to desolder them to mesure them, so in the mean time I change the mn3008 socket to be sure.

Pin 13 of MN3008 is still at 0,19 V.

Here are the back of the board. I'm ashamed of showing this mess, with all the solder/desolder the board is quite ugly now.

Thx Scruffie for your answer.

You're right, the pin 14 on the CD4047 is at 7,65V, I must have failed the first time I mesured it.

Here are some pics.

So, I've put the board back on the workbench, but still no luck.

Voltages on Pins 8, 9, 10 and 12 of the TLE2074 seems weird.
Same on the 14 of the CD4047 and 13 of the mn3008.

The first time I've tried the board, I forgot the reverse cap on the switching board, could this have damaged something somehow ?

Thank you all for the advices, I'm gonna try on the next one.

@dropanchor812 : that's exacty what i've used.

For the mudbunny, I've hesitate with this design too