Boss CE-3 LED enigma

[booj]

LED lights normally when the adaptor is disconnected. When the adaptor is used, the LED lights extremely dimly and pulsates with the chorus effect. The DC jack appears to be good and the effect works fine. The only difference is the circuit voltage is higher (about 12 volts) with the adaptor in use. Is it possible the Q11 - Q12 combo doesn't like the higher voltage?

[Jazz P Bass]

Which power supply adapter are you using?
There are some issues with power supplies.
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[g1]

Also this: ?????????????
But you state you are seeing around 12V from the adaptor, so this may not be the problem.

[Enzo]

Well how clean is that 12v?

[booj]

Wow! Super good information! thanks Jazz! thanks for the replies G-one and Enzo! The pedal is not mine. It's sheer dumb luck that I replicated the customers problem. These pedal guru's must have incredible tactile facilities. I just look at those little boxes jammed with parts and basically lose all hope right away. It makes sense to jumper R1 and the series diode, and since the power can't be plugged in backwards, no sweat about polarity damage. Thankyou!

[Enzo]

The power can't be plugged in backwards? Really?

I have been running this bench a while, and I see things all the time that had wrong power plugged into them. A guy sets up his pedal, and it is dead. First thing he does is try a different adaptor. And I guarantee the average guy has no idea that polarity matters. They bring in their pedal and adaptor, and i point out that their 6vAC adaptor won't power their 9vDC pedal. Or they grab the wrong polarity. They are amazed when I tell them adaptors come in voltages, polarities, and AC or DC.

The inevitable result is that D9 down in the corner will die shorted.

[drewl]

I've seen this on different Boss pedals.
Can't remember which pedals, but they lowered the value of the the diode series resistor.
Try a lower value for R13 (3.9K) so it pulls more current.