Hi aron, thanks for your help..
i found the 2n5457 datasheet, the fet was wired backwards..
i am now sure it is in the right direction, but it still doesn't work..
when it was backwards, the led lighted brightly , now that the fet is mounted right, it still doesn't switch off, but the led gives a really weak light..
i don't know what to do. i checked the wiring and it seems right to me, i can't see any bad soldering or misconnected elements.
i think i will desolder everything, and mount the bypass again from zero. after all, it's fun...
if you have an idea about what the problem could be.. i'd appreciate any advice.. :wink: