SOLVED Byzantium Flanger No Effect

[falco_femoralis]

Hi all, I just put together this Byzantium Flanger, but I'm having a problem. When I turn it on, I get the LED, but no effect at all. There's no boost in volume or any flanging effect. None of the knobs do anything to change the sound, same with the 3 trim pots on the back. I've tried reflowing my solder joints and double checking the values of the transistors. My chips are all legit Texas Instruments, and the BBD's are cool audio. I've attached some pics.

I had an issue with one of the solder pads for C103, so I tied in its leg to the rate control

I mounted some of the components on the back of this board, but kept their orientation in mind

Where should I start?

 

[Erik S]

Does the upper board need a ground connection through the open points next to the in and out wires?

 

[falco_femoralis]

^ I checked with a meter and there is continuity from the upper board's grounds to the bottom

 

[falco_femoralis]

I did a bunch of googling and came across one person talking about using 2n5088's for the Madbean version of this (I think, it's all a blur rn), and then I came across this

https://docs.pedalpcb.com/schematic/Schematic-Byzantium-WIP.png

Which also shows 5088's. My PCB indicates bc550's & 560's... so I guess I'm going to have to do some tracing.

There was one thread on here where the OP mentioned the same exact problem I'm having, but then he said he had a transistor in backward and it solved it. I believe the BC550's have the opposite pinout from 2n5088's so it sounds like that could be my issue

P

SOLVED Thread 'Byzantium not flanging'

Mar 15, 2024

I'm having an issue with my Byzantium where I'm not getting flanging effect. When enabled, all I hear is the input signal and none of the knobs or trim pots change anything.

I used an audio probe and noticed that there was audio going into the V3207D chip (pin 3) but no audio going out (pins 7/8). I was also expecting the V3102D chip to make some sort of noise (pulsating) by I don't hear anything when probing any of the pins. I checked the voltages of both chips and they seem reasonable, but if that would help let me know and I can post them.

I'd appreciate any help as I'm not sure what...

• punchy712
• Replies: 9
• Forum: Troubleshooting

and this shows different transistors as well

Boss BF-2 flanger guitar pedal schematic diagram

The schematic diagram of Boss BF-2 flanger guitar pedal

www.hobby-hour.com

Here's the madbean build doc (mostly for my own reference later)

https://www.madbeanpedals.com/projects/_folders/FilterMod/pdf/Fraudhacker24.pdf

 

[falco_femoralis]

Found the problem after disembowling the board, forgot to solder pin 5 of IC 5