Aion Redschift / Madbean Kezuroukai24 - selfmade pcb - issues

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Hi guys,
I made a pcb for a phaser based on Whetstone/Redshift/Kezuroukai24 and of course it is not working.

https://aionfx.com/app/files/docs/redshift_documentation.pdf

https://madbeanpedals.com/projects/_folders/FilterMod/pdf/Kezuroukai24.pdf

My schematic is attached. It's the Aion Redshift with a reduced rate selection a bit like Madbeans but not exactly.

Issues:
- VB is too low, 2.55V should be 3.58V according to the resistors and input voltage
- no modulation noticable
- signal comming out of the LM13700 is very low in volume

The first thing that I need to take care of is VB.
These are 15K and 10K, correct? The part values in general are fine...



I compared the voltages mentioned in Madbeans pdf to mine. Any hint, why VB is so low?


My OneSpot 9.47V / MB OneSpot 9.42V
9.18V Input PCB (PCB is connected on PedalPCB Protoboard)

VA 8.95V / Aion VA / MB VC 9.17V -> no VA in MB pcb
VC 8.87V / Aion VC / MB VC 9.17V
VB 2.55V / Aion VB / MB VB 4.54V

2n5088	q1	q1
c3	8.96	8.55
b2	2.45	4.26
e1	2.16	3.95

2n5087	q2	q2
c3	2.15-02.17	7.58 -> mine starts at ~2.2 then down to 2.15
b2	8.96	8.55
e1	8.95	9.17

2n7000	q3	q3
d3	4.66	7.43
g2	2.26	3.49
s1	0.825	1.69

2n5087	q4	q5
c3	5.7 - 7.3	~6.5
b2	5.0 - 7.3	6.5
e1	5.6 - 7.3	6.8

2n5087	q5	q4
c3	5.0 - 7.3	6.5
b2	4.8 - 7.3	varies
e1	5.6 - 7.3	6.8

2n5088	q6	q6
c3	8.87	9.16
b2	2.3-2.5	varies
e1	1.78-1.9	1.79

2n5088	q7	q7
c3	4.9-7.3	varies
b2	1.78-1.9	1.79
e1	1.22-1.37	~1.2

u1 LM13700
My pins	Voltage	MB pins	voltage
1	1.22-1.33	16	~1.2
2	0.7	2	-
3	2.56	14	4.63
4	2.55	13	4.45
5	3.7	12	5.46
6-	0	6	0
7	3.7	10	5.66
8	2.56	9	4.53
9	2.56	8	4.53
10	3.7	7	5.65
11+	8.9	11	9.18
12	3.7	5	5.65
13	2.56	4	4.54
14	2.55	3	4.54
15	0.7	15	-
16	1.22-1.33	1	~1.2

u2 LM13700
My pins	Voltage	MB pins	voltage
1	1.22-1.33	16	~1.2
2	0.94-0.99	2	-
3	2.55	14	4.63
4	2.44	13	4.54
5	0.38-0.46	12	5.67
6-	0.75-0.84	6	0
7	0.35-0.43	10	5.66
8	0.65	9	4.53
9	1.0	8	4.53
10	1.37-1.42	7	5.65
11+	8.9	11	9.18
12	1.44-1.50	5	5.65
13	2.5	4	4.45
14	2.55	3	4.45
15	0.92-0.98	15	-
16	1.21-1.32	1	~1.2

u3 LM13700
My pins	Voltage	MB pins	voltage
1	1.0	16	~1.2
2	1.2-1.7
3	4.9-7.3	14	~6.5
4	5.0-7.2	13	~6.5
5	2.2-2.47	12	~2.3
6-	6	0
7	0.1
8	1.8
9
10
11+	8.9	11	9.18
12
13
14
15
16

 

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Oh boy... tables are no joke. Now it's complete.

 

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When I remove the LM13700 VB drops to 1.99V !?
There is no connection from VB to any other connection (continuity tester).
The pads have been resoldered to avoid bridges between pads. I do that everytime but did it again.
I forgot th pictures yesterday.

You might notice the missing trimmer. I accidentally killed it with my soldering iron. No impact on VB. i already installed a new one.
The volume pot is supposed to look like this because the pins are mirrored.
The socket of U3 is also soldered in the wrong direction but the IC was correctly inserted.

 

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When everything is put in the sockets except for Q6 & Q7 then VB also drops.
I desoldered parts I added parts, still the same result. It must be some really small stupid error I made...