BOSS SYB-3 schematic??

[Bernardduur]

Hi all;

I have just gotten a very cheap Boss SYB-3; one problem: it does not work like it suppose to. In mode 1-7 (internal sound modes) it does not track any pitch, only attack. I'm trying to fix it.... The other modes work just fine

Anyone has a schematic or knows what's wrong?

[Paul Perry (Frostwave)]

It's a digital effect, so that is something to take into consideration... the first thing I would do, is make sure that all the controls work for at least SOME settings. If that is the case, then the fault can only be a digital PCB trace, or chip connection (there can't be anything wrong with the DSP core, or NOTHING would work).
At least, that is my view... unless there is some analog signal perparation going on before the signal goes to the analog input to the DSP specifically for pitch determination.
The other thing about the SYB-3..... don't even THINK about running it on batteries. Unless you live in India & are very rich, and employ a battery-wallah.

[Bernardduur]

Yes, I know, it is so weird.

The guy I got it from states it worked just fine before he gave it to me...... Now some settings are just dead;

Mode 1, 4, 5 and 7 does not work at all; no sound is produced.
Rest of the modes works just normal but one fault: no pitch tracking....... I only get a sound with the "A" pitch (440) witch it quite frustrating (getting the same sound over and over and over and over); attack tracking is normal.

Mode 8 and 9 work just fine
Mode 10 and 11 work just fine

I've put it on different PSU's (from my DC brick, my Cioks baby and a battery) but all give the same result.
I've also used different guitars, basses and all..... still the same result.

Inside looks just normal; no weird views. All is SMD and chips (can make some pics if someone wants).

[Paul Perry (Frostwave)]

Found this at a review site (harshnoise): "Internal synth settings 1 - 7, will cut out entirely with escessive input volume, must be externally triggered (though this may be a plus for some)."

[Bernardduur]

Yes, I've also read that and tried stuff with the input volume

Still no results