ricothetroll
Well-known member
hi, i built a 4-channels green pre. everything works fine, excepted the led meter of one of the preamps (everything works on this preamp excepted that).
i built the v14 of the green pre.
i tested a few things but didn't manage to find where the problem is:
- i changed the 4 leds
- i switched the tl074 and the lm339 with another preamp : the other one works still fine and the problematic one still doesn't work
- i measured the voltages on the pins of the tl074 and the lm339 and some aren't the right ones : pin 11 of the tl074 and pin 1, 2, 12, 13, 14 of the lm339.
as i found no scheme of the v14 i don't know exactly which parts of the circuit are concerned with the led meter. of course, i compared the problematic circuit with the 3 others but i found no difference...
can someone help me with this?
thanx a lot.
i built the v14 of the green pre.
i tested a few things but didn't manage to find where the problem is:
- i changed the 4 leds
- i switched the tl074 and the lm339 with another preamp : the other one works still fine and the problematic one still doesn't work
- i measured the voltages on the pins of the tl074 and the lm339 and some aren't the right ones : pin 11 of the tl074 and pin 1, 2, 12, 13, 14 of the lm339.
as i found no scheme of the v14 i don't know exactly which parts of the circuit are concerned with the led meter. of course, i compared the problematic circuit with the 3 others but i found no difference...
can someone help me with this?
thanx a lot.