TC Electronic BLD Booster Line Driver, weird bypass/LED troubleshooting

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Post by Visualdistortion »

Hi guys,
I get a broken BLD pedal few months ago, after get a sound. by changing few components, I leave it until now.
So I try to fully repair it, so this is the actual repair I've done on it:

- The pedal now have a standard round dc jack (like almost the boutique pedals)
- Changed IC for TL074CN and a HEF4007UBP
- Few diodes for 1N914 from the power/switching section (I don't have any 1N4148 actually)
- I also changed the BC558 on the switching section for a 2N3906 (pinout is reversed)
- The circuit is out from the box, I've connected a momentary toggle from switch wire to ground (jack sleeve) to make a footswitch simulation.

My problem is about the power of the pedal, normally when you have battery on it and you turn the pedal on, 10s after the led stop to light (effect is working by the way) and when you use a power supply the led need to works normally like all the pedals in the world, but mine have the same "led goes off" tricks on battery or power supply.

The original DC Jack have a tip (+) sleeve (-) and break connection when power is used, by using a normal DC jack I can't break the connection on sleeve side, and how to wire this lonely pad, I don't know if it's the problem here but it can be a clue.

There is the original schematic and parts pdf: ... _boost.pdf

Mine is in attachement

There is some guts found on internet: ... /image&r=1

Thanks a lot for your help, I become a bit crazy with this one.
I wanna make it
I wanna make it wit chu
(again and again and again)

French... sorry ;)

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