Dirtbag Troubles

[LaceSensor]

I got it! Pin 12 of the Compander, it's set to bias the output of the Compander and it's still set for 15V so the compander is putting too much signal back into the feedback path and clipping your delays!

Well at least I think that's what's going on and i'm not about to be an idiot when you both say that didn't help at all.

Right, try half the value of 11k (5k6, 4k7, something round there) and then try again.

I'm about to start building this for v3205s and have been reading this thread with interest (and trepidation haha) - are you saying the 11k value of R42 is definitely wrong if building the V3205 for 9V operation?

Probably just wait or socket a load....

[LaceSensor]

Ok so I tacked on an 11k in parallel with the existing

(11 x 11) / (11 + 11) = 5k

The sound on pins 3 of the BBD seem to be a bit cleaned up.  
However, the pedal just passes straight signal, no echos.

All the other mods back to normal (r11 and r12 47k, tried with 33k same deal )

it was at least delaying when I left it last night.

voltages for the compander now.

Before                 after "changing" r42
IC2 SA571N
1-1.28                 1.05
2-1.80                 same
3-1.80                 same
4-0                     same
5-1.80                 same
6-1.79                 same
7-7.43                 7.40
8-1.80                 same
9-1.80                 same
10-8.05               8.20
11-6.37               6.30
12-1.81               1.24
13-8.98               same
14-1.80               same
15-1.80               same
16-0.27               0.39


edit - if I untack that resistor bringing down to 5k, I get my repeats again....

ive got a feeling we might be some time here.

Im a bit sad we havent heard from Madbean again on this one. This is probably the most anticipated pedal of the DIY calendar year

[tenwatt]

You keep beating me to the punch, Lace.  You must have a lot more free time than me. 

[LaceSensor]

I just got up and gave it a whirl today

Its a quiet week (working from home).

If you wanna replicate it, thatd be nice to know we are both in the same boat.

For what its worth, no offence to people helping, but I think I wanna take a break now until we can (hopefully) get a final say on whats gone wrong here. Too coincidental for it to just be something we have done, and I can say (apart from the clock Cap, and the 1n2, which I made 1n) I have built this 100% to spec so its probably gonna be something needs fixing in the BOM and until we can get a final say on that, im scared if I keep butchering my board its gonna get damaged and Ive worked to hard on this to ruin it now and need to buy everything again.

Hopefully Bean is beavering away with his board and can chip in.

[tenwatt]

Hey Lace, the guys on this board usually try not to bombard us with info.  My guess would be that Brian's advice would be the same that we are already receiving or he's just really busy right now.  Plus, I'm not sure that the PCB and instructions are the problem.  It could still very well be something we did in assembling the circuit.

With that being said...I have some crazy problems.  Here are my voltages.  Any advice would be GREAT!

VC: 9.4V

IC1
5.08
5.08
5.07
1.8mV
9.4
5.08
5.08
5.04

IC2
1.15
1.81
1.81
1.4mV
1.81
1.81
7.83
1.81
this pin goes crazy and the meter jumps all over the place
1.81
1.81
9.4
1.81
6.12
7.84
1.81

IC3
5.08
5.08
5.08
0
9.4
5.08
5.08
5.08

IC4
1.4mV
4.71
5.9
5.9
7.93
5.55
4.71
8.2

IC5
1.4mV
4.71
5.58
5.58
7.92
5.33
4.71
8.2

IC6
5.33
5.33
5.32
1.4mV
9.40
5.58
5.35
5.31

IC7
this pin goes crazy and the meter jumps all over the place
4.78
4.46-5.2 (this pin also jumps around)
.5mV
9.4
4.46-5.2 (this pin also jumps around)
4.78
4.78

IC8
5.09
5.09
5.07
0
9.4
7.84
7.84
7.76

IC9
4.34
5.02
5.08
9.4
9.4
9.4
.9mV
9.4
4.38
1.3mV
4.71
4.71
1.3mV
1.3mV

[Scruffie]

Hey Lace, the guys on this board usually try not to bombard us with info.  My guess would be that Brian's advice would be the same that we are already receiving or he's just really busy right now.  Plus, I'm not sure that the PCB and instructions are the problem.  It could still very well be something we did in assembling the circuit.

With that being said...I have some crazy problems.  Here are my voltages.  Any advice would be GREAT!

IC7s Pins should be moving, it's the LFO, that's normal.

But it seems your other problem is with the Compander (IC2) I stand by that area being a issue but untill my full nets back on the 15th, I can't get a copy of the compander datasheets or cookbook.

Your 4047 (IC9) voltages are wayy off though, are you sure you haven't written them down wrong? 4 of the pins should be ground, 10&11 should be roughly half supply and why are most of your grounds at 1.4mV?

Everything following the first stage of the compander has 1.4mV of ground untill the path comes back to the compander and it's okay gain from IC8.

I just got up and gave it a whirl today

Its a quiet week (working from home).

If you wanna replicate it, thatd be nice to know we are both in the same boat.

For what its worth, no offence to people helping, but I think I wanna take a break now until we can (hopefully) get a final say on whats gone wrong here. Too coincidental for it to just be something we have done, and I can say (apart from the clock Cap, and the 1n2, which I made 1n) I have built this 100% to spec so its probably gonna be something needs fixing in the BOM and until we can get a final say on that, im scared if I keep butchering my board its gonna get damaged and Ive worked to hard on this to ruin it now and need to buy everything again.

Hopefully Bean is beavering away with his board and can chip in.

I don't blame you, no point ruining the board.

This is something that should be done on a breadboard and by someone with the datasheet in front of them, not someone trying to go from memory, shame though, thought i'd had a bit of a moment but I THINK that's the area to keep digging in, it makes sense.

My next suggestion woulda been to remove R42,43 & 27 from that area... if you wanna risk it, that's my final suggestion.

[LaceSensor]

any thoughts on why dropping that R42 to to 5k would stop all the echoes being heard?

Like i said it seemed to be having a positive effect when audio probing the BBDs.

my problem now is

1- dont wanna ruin the board. Whats the most efficient and risk free way to desolder these double side boards?

2- replacing sockets where there were resistors in tight packed areas is not always easy due to space.
Id have to start from scratch and socket those to do a clean job. I know it doesnt matter in the long run, but a board I was really pleased/proud of is now getting chopped up and replaced with loads of sockets... 

[jubal81]

I'm not as far in the debug process as you guys, but I'm also having the same problem.
Echos are nasty distorted and no amount of biasing can clean them up.

No advice to give. I set it aside yesterday so I wouldn't get frustrated with it.

[LaceSensor]

sorry to hear that genuinely
however in a selfish way its almost heartening to not be on your own

[tenwatt]

Your 4047 (IC9) voltages are wayy off though, are you sure you haven't written them down wrong? 4 of the pins should be ground, 10&11 should be roughly half supply and why are most of your grounds at 1.4mV?

Everything following the first stage of the compander has 1.4mV of ground untill the path comes back to the compander and it's okay gain from IC8.

Yeah, I'm wondering the same thing.  I don't think I wrote them down wrong.  I'll recheck tonight.  About the grounds...I really don't know what's up.  Any ideas on what I should check?  I wonder if it has anything to do with the whining "Delay" pot (It only whines when turned past the halfway point and stops when I touch the "Level" pot).

My next suggestion woulda been to remove R42,43 & 27 from that area... if you wanna risk it, that's my final suggestion.

Lace, I won't be able to get to this until late tonight or tomorrow.  If you need a break and want to wait for me to try it...by all means...take a break.

Scruffie, would we simply remove them?  Do we need to add any jumpers?

[LaceSensor]

Cheers dude

Yeah I am pretty burnt out now.
Like I said earlier, until its resolved one way or another, its in a cupboard.

Wonder if anyone have build the current lover yet. not sure I wanna be an "early adopter" again...
. In any case I think I am gonna give building a rest for a while

[Scruffie]

Cheers dude

Yeah I am pretty burnt out now.
Like I said earlier, until its resolved one way or another, its in a cupboard.

Wonder if anyone have build the current lover yet. not sure I wanna be an "early adopter" again...
. In any case I think I am gonna give building a rest for a while

I bet you are, cheers for trying everything! Very good of you to help and try and get this one going smoothly.

I'm pretty sure the Current lover is fine, I saw a build report and it's wayyy less complex than this.

I'm not as far in the debug process as you guys, but I'm also having the same problem.
Echos are nasty distorted and no amount of biasing can clean them up.

No advice to give. I set it aside yesterday so I wouldn't get frustrated with it.

Right, three cases, there's definitley something going on.

Lace, do you have sockets for R11 & 12? I know you're out the game but if there's sockets it'd save someone else desoldering, if so, one last try, put 24ks in both. Really the output of the Compander should be biased to 1/2 supply so 7vish is rather high.

If someone looks at the datasheet, you can find out what to do about Pin 12 (R42) I think I got it wrong from memory as the output voltage climbed to 8.2V so in fact you should increase it... if you try 24k in there.

We want both outputs around half supply.

Ignore what I said about removing R42,43 & C27.

I'm now positive the Compander is the issue, it's just feeding too much signal back in to the BBD.

Tenwatt... i'm afraid your voltages are a little more concerning.

[tenwatt]

Tenwatt... i'm afraid your voltages are a little more concerning.

Any ideas?  I'll remeasure it tonight.

[LaceSensor]

Cheers dude

Yeah I am pretty burnt out now.
Like I said earlier, until its resolved one way or another, its in a cupboard.

Wonder if anyone have build the current lover yet. not sure I wanna be an "early adopter" again...
. In any case I think I am gonna give building a rest for a while

I bet you are, cheers for trying everything! Very good of you to help and try and get this one going smoothly.

I'm pretty sure the Current lover is fine, I saw a build report and it's wayyy less complex than this.

I'm not as far in the debug process as you guys, but I'm also having the same problem.
Echos are nasty distorted and no amount of biasing can clean them up.

No advice to give. I set it aside yesterday so I wouldn't get frustrated with it.

Right, three cases, there's definitley something going on.

Lace, do you have sockets for R11 & 12? I know you're out the game but if there's sockets it'd save someone else desoldering, if so, one last try, put 24ks in both. Really the output of the Compander should be biased to 1/2 supply so 7vish is rather high.

If someone looks at the datasheet, you can find out what to do about Pin 12 (R42) I think I got it wrong from memory as the output voltage climbed to 8.2V so in fact you should increase it... if you try 24k in there.

We want both outputs around half supply.

Ignore what I said about removing R42,43 & C27.

I'm now positive the Compander is the issue, it's just feeding too much signal back in to the BBD.

Tenwatt... i'm afraid your voltages are a little more concerning.

Hi

I did socket R11, R12 and  R21
I can try 24k gimme a moment.

With regards upping the resistor at R42, ill tack something to approximate 24k there as well.

Cheers.

[LaceSensor]

actually unless my maths is shit its going to be hard pushed to make a parrallel resistor work with the 11k already in place..

right?