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it always feels great after some quite time for debugging, and finally got it working. plus this is my first take on modulation effect. so yes, really enjoyed the moment  .

Bret, I'm using old file from project archive, on the PDF it said Pork Barrel ver2.0. it was for MN3007 only.
meanwhile the latest Pork Barrel could use both MN3007 and MN3207.
I showed the MN3207 just for comparison  .

by the way, the Pork Barrel now working   .
just like Scruffie said, the BBD seems okay, and indeed they all okay.

I don't know what's wrong, I'm about to use audio probe. and before I did that, I tried it one more time, and voila, it's working!

thank you for all of your input guys .

now I can move on to another modulation effects, crazy about modulation lately.

ok, I'll try to trace with audio probe,

meanwhile, these are my BBD.

MN3007:




MN3101:




got the MN3207/MN3102 from working unit karaoke mixer machine, so they're suppose to be genuine.
the MN3101 looks suspicious since it looks different from the other.
meanwhile the MN3007 has similar appearance with the MN3207/MN3102, although the font color slightly less visible than the MN3207/MN3102.

ok, fix the problem on IC1. follow Scruffie instruction and play around the trimpot.
and finally, I can get Vref from 2v-5.5v using the trimpot.

I can get clean signal right now, but still no chorus. and went silent if I switched to vibe mode.

here is my updated voltage chart (trimpot set full clockwise):
IC 1 (JRC4558D)
1 = 5.4v
2 = 5.4v
3 = 5.4v
4 = 0v
5 = 5.4v
6 = 5.4v
7 = 5.4v
8 = 9.08v

IC 2 (TL062)
1 = 3v - 6v (fluctuating, approximately)
2 = 4.58v
3 = 3.8 - 5.2v (fluctuating, approximately)
4 = 0v
5 = 4.58v
6 = 4.6v
7 = 3.8 - 5.2v (fluctuating, approximately)
8 = 9.08v

IC 3 (MN3101)
1 = 9.08v
2 = 4.63v
3 = 0v
4 = 4.67v
5 = 0.33v
6 = 8v
7 = 2.7v
8 = 0.6v

IC 4 (MN3007)
1 = 9.08v
2 = 4.66v
3 = 4.72v
4 = 0.6v
5 = 0v
6 = 4.63v
7 = 4.58v
8 = 4.58v

Q1 (2N5088)
E = 3.68v
B = 4v
C = 9.08v

Q2 (2N5088)
E = 4.19v
B = 4.7v
C = 9.08v

Q3 (2N5088)
E = 3.79v
B = 4.22v
C = 9.08v

Q4 (2N5088)
E = 0v
B = 0.28v
C = 8.49v

Q5 (2N5088)
E = 2.2v - 3.1v (fluctuating, approximately)
B = 2v - 3.6v (fluctuating, approximately)
C = 9.08v

thank you for any input

Why does everyone always assume the worst for the BBD...

Issue is IC1, wont work like that, something is messing up the voltages on it, should have approx half supply on pins 1,2,3,5,6 & 7.

LFO & Clock seem good.

No time to dig deeper this second but your V.ref might be going wrong (measure it at lug 2 of the trim) or you orientated  the cap in for it backwards maybe... or something in its path or round IC1 is causing an issue.

hi Scruffie, thank your for your input.
first time using BBD, so I'm not quite familiar.
the MN3101 looks different from usual MN3101 that I saw on various pics, so I thought maybe it's not genuine.
will try to look on the IC1

hi, I just build a Pork Barrel, but sadly, it didn't work.
perhaps somebody can help me sort this thing out.

(1) Project Name: Madbean Pork Barrel (file ver.2)

(2) General description of the problem
only produce crackling noise

(3) Steps that you have taken to try to resolve the issue
retrace the pcb path, check the solder join, check for any short/bridging, check connections

(4) List any substitutions you used for parts/values
used same value as listed BOM

here is what I've got on voltage measurement (power supply Tonepad LM317 regulated):
IC 1 (JRC4558D)
1 = 9.11v
2 = 9.09v
3 = min 0.13v, max 0.44v (from VB trim)
4 = 0v
5 = min 0.13v, max 0.44v (from VB trim)
6 = 8.79v
7 = 8.8v
8 = 9.17v

IC 2 (TL062)
1 = 1-7.9v (fluctuating, approximately)
2 = 4.4v - 4.7v (fluctuating, approximately)
3 = 3.2v - 6.1v (fluctuating, approximately)
4 = 0v
5 = 4.4v - 4.7v (fluctuating, approximately)
6 = 4.5v - 4.7v (fluctuating, approximately)
7 = 3.3v - 6.2v (fluctuating, approximately)
8 = 9.17v

IC 3 (MN3101)
1 = 9.1v
2 = 4.63v
3 = 0v
4 = 4.66v
5 = 0.25v
6 = 8.25v
7 = 2.5v - 2.9v (fluctuating, approximately)
8 = 0.59v

IC 4 (MN3007)
1 = 9.11v
2 = 4.66v
3 = 2.5v
4 = 0.59v
5 = 0v
6 = 4.63v
7 = 2.86v
8 = 2.86v

Q1 (2N5088)
E = 7.45v
B = 8.15v
C = 9.17v

Q2 (2N5088)
E = 2.63v
B = 3.15v
C = 9.17v

Q3 (2N5088)
E = 0v
B = min 0.13v, max 0.44v (from VB trim)
C = 9.17v

Q4 (2N5088)
E = 0v
B = 0.28v
C = 8.49v

Q5 (2N5088)
E = 1v - 3.2v (fluctuating, approximately)
B = 1.7v - 3.9v (fluctuating, approximately)
C = 9.11v

anyone can help me?
I got the BBD from eBay (China/Hong Kong), fake chips perhaps?
or there are other problem?

thank you