News:

Forum may be experiencing issues.

Main Menu

currant lover debug

Started by Kipper4, May 13, 2014, 07:22:25 PM

Previous topic - Next topic

Kipper4

guys
i have the currant lover all populated and set up to start biasing it as per pdf.
I'm not getting a signal on the output.
so I start probing and the signal goes as far as mn3007 pin 3. no output on pins 7 or 8.
I bought my chips on ebay. could I have bought a fake. Do you think that could be the reason.
I've invested a lot of time and money and effort into this one effect, the biggest most complex build to date and I'm bitterly dissapointed. I hope I havent blown it all together.
one other thing i've noticed is if i disconect the gnd to amp i get a signal.
Please help. If its just a matter of getting a better mn3007 then fine.
I'm building it on a prefab qaulity pcb.
thanks
Rich

Govmnt_Lacky

Lots of questions here....

Are you getting bypass signal? Did you run through the range on the BIAS pot? What are you IC voltages and what were your pots set at when you took them? Could you explain a bit more about " if i disconect the gnd to amp i get a signal?"

Posting some IC voltages is the next step to full enlightenment  8)

Kipper4

i didnt fiddle with the bias pot yet. as the instructions say i should get signal with tit set half way up.
its not boxed yet just on my test rig so no bypass. although i checked the cabling and did some probing .
settings of pots as at pdf here
http://www.madbeanpedals.com/projects/CurrentLover/CurrentLover.pdf

Enlighten me please
power supply 9.13v
ic1                                                                 ic2
1   4.59             5    4.52                                1   9.12         5    0
2   4.59             6    4.57                                2    4.56        6    4.55
3   4.17             7    4.54                                3   2.38         7    3.72
4 0                    8    9.13                                4   0              8    3.75

ic3
1   9.13          9    4.55
2   4.47         10   4.56
3    4.53        11   4.55
4   4.55         12    4.55
5    4.51        13    0
6    4.54        14    4.55
7    4.55        15    4.53
8   0               16    0

ic4

1   4.62     
2   4.54
3    8.8 to 6.9
4    0
5     4.55
6-12   0
13   9.12
14   9.12


ic5

1   4.56               8    7.89 to 0.5
2   4.56               9    4.3 to 4.1
3   4.52             10    6 to 2.5
4   9.13             11    0
5   1.9 to 1.1     12   4.28 to 4.2
6   2 to 1.1        13   4.28 to 4.1
7   5.2 to 1.1     14   3.3 to 5.4


ic6

1    0                5   9.13
2   1.2 to 4.3    6   9.13
3   0.9 to 3.4    7   8.8 to 6.9
4  0                   8    9.13

Govmnt_Lacky

From the start, I can see that your input signal into the MN3007 (Pin 3) is really low. You need to adjust the bias and get that voltage higher (I would guess around 4.5-5.5VDC)

Quick question....

Are you absolutely positive you followed Brian's steps for setting the jumpers and component installation for the MN3007? (Instead of the MN3207)

If yes, then you need to tweek the BBD bias trimmer for sure  ;)

Also.... take your measurements with the pedal in MATRIX mode. It eliminates the LFO so there is no fluxuation in the voltages. It also allows you to measure your minimum and maximum clock values without having to worry about the wobble (these are measured at the BBD clock input with the Range pot at full CW and full CCW)

Kipper4

Well Lacky you'll be pleased to know its working now.
you were spot on one I got in the region of 4.5v on pin three of the MN3007 i got signal.
Now I've even got it flanging although I think When I get time I'm gonna tweek it better.
Thanks for the help. Most appreciated.
Having not really worked with the mn3007 before (exception being the tonepad Chorus) I wasnt aware of what to do. Now i think I've learn something today.
Onwards and upwards
Rich

Govmnt_Lacky

Good deal!!!

Definitely try to tweak it so you can get the most out of it  ;)

Kipper4

Tweeted it some and it's excellent.
I can't see me making much use of the matrix but I need to experiment some with it.