Current lover weird modulation

[jkokura]

So that's weird. If you had it working outside the enclosure that immediately makes me think that something is either grounding against the enclosure OR there's a problem with your power and wiring. Take it out of the box, does it work again?

Jacob

[djaaz]

It has been out as soon as i realized i had an issue and it was not related to the wiring.

Is there anyone out there that has a working current lover and would not mind to share its IC's voltage?

Next step for me would be to change all the ICs just in case. The MN3007 price hurts a bit though.

[djaaz]

Hi guys,
Today i replaced jrc4558, cd4049, 4013 & lm324 and no changes.

Should i try to replace MN3007 or for the same price order another PCB?

What do you think?

[jkokura]

I think that since it was working before, you need to figure out what changed. Really, I'm not sure what else to tell you. You could try replacing your MN3007, but depending on where you got yours from it may not be the problem.

Jacob

[djaaz]

The MN3007 is coming from musikding.de a usually very reliable source.

And that's the thing: Nothing changed. The only significant event i can think of is the 3-5 seconds i plugged the inverted polarity power supply (the one i use for the cap meter i built)
This is why i'm thinking maybe a damaged chip.

Will put this thing in a box & wait for the devil that is sitting on it to go away.

Thanks Jacob.

[jkokura]

Have you checked your polarity protection diode? If you did that, even briefly, that's what could have caused the problem. I don't know if you mentioned that already or not, but hearing that could change everything. Check D3 and the other parts in the power section.

If that's not it, I don't know what to tell you except unsolder all your wires, put a new MN3007 in, and redo the wiring to see if that helps.

Jacob

[djaaz]

Yes i wrote it before but i guess i wrote a lot and surely too much.

I'm struggling with the power section. I don't get what to do with this part of the schema for instance:



what am i supposed to check?

I checked  CD4013 & LM324 already

Suppose i should check c20, LM311, D2, D3 & D4 as well?

and then this silly question, how to check that a diode works? Using a dmm in ohmmeter mode?

[LaceSensor]

I have built a working CL.
I can do the voltages but require ecookie as payment 

[lloyd17]

I just finished up my PCB and can make it sound the same way yours does in the video by messing with the bias and clock pots. It actually can do some pretty interesting stuff at the bottom of the sweep when the trims are set really wrong. I'm still dialing it in and bias/clock each seem to move the others sweet spot. Pretty sure it was there for a few minutes until I screwed with it attempting to 'improve' things

I can get it most of the way there but have some trouble reconciling the trims with feedback and range both above around 80%. Then again that might be what happens when you start turning knobs all the way up!

Just a thought, good luck man.

[djaaz]

HEre you go, Lace. And thanks!




And thanks Lloyd17.
I played with the trimmers yesterday and indeed having the clock trimmer all the way down between 7 & 8h30 makes the "detunes" disappear but so does the flange.

The bias trimmer needs to be almost all the way up to have some effects without distortion.

[LaceSensor]

ill post voltages today

[djaaz]

Thanks guys!

Any interest for another video, may that help?

[madbean]

Kind of a stumper. I'm leaning towards a biasing adjustment being needed, too. Sounds like the LFO is doing what it needs to do, and the MN3007 is doing it's thing, but it won't bias properly. I don't think you need to replace the MN3007.

First thing I would do is socket C18 and try some other values there...15pf, 33pF, 47pF. This should help "reset" your clock trimmer. Try that and let us know what you find.

[LaceSensor]

From memory Im keen to agree with bean and lloyd
I found when I was building mine I messed a lot with the trimmers, and could get some really odd modulation going on. Could be normal. Listening to the video you posted I think it sounds normal kinda (!)

Not sure, depends what everyones expectations of the circuit are.

[LaceSensor]

Thanks for the cookie
Here the goods

supply - 9.4V

LM311
1-0
2-varies
3-varies
4-0
5-9.2
6-9.3
7-varies
8-9.2

MN3007
1-9.4
2-4.2
3-3.6
4-0
5-0
6-4.6
7-3.6
8-3.7

JRC4558
1-4.9
2-4.7
3-2.3
4-0
5-4.2
6-4.7
7-4.7
8-9.3

4049
1-9.3
2-4.5
3-4.5
4-4.5
5-4.6
6-4.5
7-4.6
8-0
9-4.6
10-4.4
11-4.6
12-4.6
13-0
14-4.7
15-4.7
16-0

4013
1-4.6
2-4.6
3-7.4
4-0
5-4.6
6-0
7-0
8-0
9-0
10-0
11-0
12-0
13-9.2
14-9.2

LM324
1-4.6
2-4.6
3-4.2
4-9.2
5-1.4 - 2.0 ish
6- varies
7- varies
8-jumps 0.6 up to 7.5 and back
9-4.2
10-varies
11-0
12-4.2
13-4.3
14-varies

Hope that is of use