Author Topic: Madbean Total Recall is driving me nuts!  (Read 703 times)

Scruffie

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Re: Madbean Total Recall is driving me nuts!
« Reply #15 on: March 20, 2019, 02:21:45 PM »
Bias 2 affects the biasing of IC4, does adjusting it change the distorted signal you get at pin 7?
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Ariosto

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Re: Madbean Total Recall is driving me nuts!
« Reply #16 on: March 23, 2019, 03:24:33 PM »
Bias 2 affects the biasing of IC4, does adjusting it change the distorted signal you get at pin 7?

I can say you next Monday, because I forgot the power supply in the Music School where I work. By the way, do you have experience with the Aquaboy Delay? I experienced a very strange issue with mine.

Ariosto

Ariosto

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Re: Madbean Total Recall is driving me nuts!
« Reply #17 on: March 27, 2019, 02:57:59 PM »
Bias 2 affects the biasing of IC4, does adjusting it change the distorted signal you get at pin 7?

Scruffle! H  E  L  P   !!!!!! With the audio probe I get audio signal (distorted and with a throbbing pulse included) only in IC6. No signal in IC4, neither in IC7. I think the pedal is bewitched. Must I desolder the whole components and begin everything from the beginning again?

Scruffie

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Re: Madbean Total Recall is driving me nuts!
« Reply #18 on: March 27, 2019, 03:09:03 PM »
Throbbing pulse sounds like the modulation is on.

So on pin 7 of IC6 you get cleanish audio signal, yes? Have you adjusted the bias trimmer while audio probing its output?
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Ariosto

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Re: Madbean Total Recall is driving me nuts!
« Reply #19 on: March 28, 2019, 03:23:06 AM »
Throbbing pulse sounds like the modulation is on.

So on pin 7 of IC6 you get cleanish audio signal, yes? Have you adjusted the bias trimmer while audio probing its output?

Yes, it means clean audio signal WITHOUT delay. It sounds a bit distorted but I guess that it is normal... I tried adjusting both BIAS trimmers in search of audio signal in the following ICs but nothing happened.

zgrav

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Re: Madbean Total Recall is driving me nuts!
« Reply #20 on: March 28, 2019, 12:24:34 PM »
Don't worry that you do not yet have a working project.  You picked a very difficult build even for an experienced builder, and it would not be unusual for that person to have to find and fix problems to get it working. 

Your board is (probably) not bewitched, but it is a complex build that might have more than one issue in it that you will need patience to find and fix.  You already have corrected the big problem of trying to build the board with two different sets of memory chips where only one of the two sets is supposed to be used.   Any time you find and fix a problem you can see if the board works, and if it does not start over looking for the next problem.

Go back and measure all or your voltages again and see what you get because removing the extra set of memory chips may have changed some of those voltages.  Then check to make sure you have good ground connects on the board for the different parts of the circuit diagram that shows a connection to ground.    It may take a while to work through these issues, so don't worry if you set it down for a while and go build another project where you might learn a bit more that will help you get this one working.  It helps to realize that you probably have 99% of the board put together correctly and you just need to find a fix a few things to get it working.

Ariosto

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Re: Madbean Total Recall is driving me nuts!
« Reply #21 on: March 28, 2019, 02:32:09 PM »
Don't worry that you do not yet have a working project.  You picked a very difficult build even for an experienced builder, and it would not be unusual for that person to have to find and fix problems to get it working. 

Your board is (probably) not bewitched, but it is a complex build that might have more than one issue in it that you will need patience to find and fix.  You already have corrected the big problem of trying to build the board with two different sets of memory chips where only one of the two sets is supposed to be used.   Any time you find and fix a problem you can see if the board works, and if it does not start over looking for the next problem.

Go back and measure all or your voltages again and see what you get because removing the extra set of memory chips may have changed some of those voltages.  Then check to make sure you have good ground connects on the board for the different parts of the circuit diagram that shows a connection to ground.    It may take a while to work through these issues, so don't worry if you set it down for a while and go build another project where you might learn a bit more that will help you get this one working.  It helps to realize that you probably have 99% of the board put together correctly and you just need to find a fix a few things to get it working.

Thanks a lot for the advice! I must take a deep breath, make a pause and come back to the "operation table". Well, step 1 should be measuring the voltages again. What I donīt know is how to detect if an IC is dead or not. Another way to find the problem could be using an audio probe from the output back to the input, but as already said, I become audio signal when the effect is engaged, the "Level" and "Blend" potentiometers are working correctly obviously without delay signal......