Deluxe Memory Man Clone - No wet sound / Troubleshooting

[fedevespa]

Hello everybody,

I have built a clone of the Memory Man following this schematic: http://www.op-electronics.com/en/delay-reverb-and-chorus/478-deluxe-delay-8000478244076.html and, well, it doesn't work 
So, I'll try to explain my problem: the pedal is working, but just with the minimum level of delay, which sound more as a reverb. As soon as I turn the "Delay" knob up, I hear a swap and the wet sound is gone. The dry sound is no problem at all, nor the modulation section. A couple of infos:

- I am using two Xvive MN3005
- I am powering the pedal at 12 V; I tried to power it at 9 V, and in this case no wet signal at all
- no bad solder joints are present (I checked like 8 times)
- I can get up to 7 V on Pin 3 and 4 of the two MN3005s, and also the BIAS is working since I can adjust it
- the signal led works when I play notes on the guitar, or when I put the feedback to MAX and let the sound saturate

Do you have any idea? Any help is highly appreciated!

Greetings from Germany,
Fede

[Vitrolin]

As I recall MN3005 runs on negative 15V. un like MN3205 that uses a positive supply.
so any positive voltages on MN3005 is a problem.

[Kevin Mitchell]

Yeah the link for that board says "mn3205". So you have the wrong BBDs. However one could do a work-around. Just have to swap the power and ground pins so the polarity accommodates the mn3005s. I suggest you file away those connections and put jumper wires in place to fix it up. Or make a daughter board with vero or stipboard to rout the connections you need.

How can you bias a BBD that isn't working?.....

Anyways... Msg me if you need more details and I'll break it down for you.

[fedevespa]

Thank you for your replies!
Well, the project can work with MN3005. Indeed, you just have to connect 3 jumpers on the board in the right manner (see pag. 1 of the datasheet, at the bottom). And I think I did it right, since the voltage on Pin 3 and 4 changes as I move the "BIAS"pots.. Or am I wrong and should I read a negative voltage on the MN3005s? Maybe you can have a look at the voltage chart and tell me if the values make sense (all values from Pin 1 and then up):

Voltage: 12,3 V

IC1 (TL072P)
6,47
6,47
6,47
0
6,47
6,47
6,47
12,3

IC3 (TL072P)
6,47
6,47
6,47
0
6,47
6,47
6,47
12,3

IC6 (TL072P)
6,6
6,6
5,5
0
6,7
6,7
6,9
12,3

IC8 (TL072P)
6,47
6,47
6,47
0
3,48
3,51
3,5
12,4

IC2 (NE570)
1,2
1,8
1,8
1,8
1,8
9,8
1,8
1,8
1,8
3,5
3
1,8
12,3
1,8
1,8
0,8

IC7 (TL062P)
5,3
6,2
6
0
6,2
5,9
6,5
12,3

IC9 (CD4047)
6,7
5,5
5,6
12,3
12,3
12,3
0
0
0
5,9
5,9
0
6,7
12,3

IC4 (MN3005)
11,72
5,89
4,14
4,13
0
5,88
6,3
0

IC5 (MN3005)
11,72
5,89
4,0
3,9
0
5,88
6,7
0

I am pretty sure that some of them do not make sense at all (see e.g. NE570)