Need Help Fixing a Boss DD3 Long Chip

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Post by Leder »

Hello everyone!

I bought an 1989 MIJ Boos DD3 long chip version that didn´t work. After doing some measuring i recap all electolitycs and the pedal come back to life. But (allways a but) when the pedal is on i only have delay signal on the output. Studying the service manual i notice that Q8 and Q5 switch between on/off for stereo mode when you plug direct out and output at the same time. I don´t understand why Q5 its working like this and i don´t know where to continue lookinf for the fault. Q7 its obviuos that it works, because Q5 can go on and off. Therefore, could it be that the flip flop (Q9) is malfunctioning? How do I find out?

I attach the servie note manual.

Thank you a lot!
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