So my Lexicon DC-2 processor has developed this problem where only scratchy static noise is been put out on any of its output. What do you thing it could be? any help or suggestion will be appreciated.
I would check for missing analog supplies at opamps (I would expect + and -12 to 15 V to be present) first, and in a similar vein, missing +VA at the DACs. A voltage regulator might have called it quits. This is affecting both analog and digital inputs, right?
I was unable to find a service manual for this unit, but apparently the power supply section is shared with the DC-1, for which you can find one on HiFiEngine, and I'm assuming the general architecture won't be entirely different. Notably, that one derives its DAC +VA from +5VD, and there's an additional pair of +/-5VA to power a bunch of PGAs which are being derived from +/-15 V. So definitely start there.
No details are being provided on the mains power supply side so I suspect it is a SMPS module sourced externally. If you have no prior experience working on these, go watch some videos on SMPS repair, keep your distance from the primary side, and if +/-15 V turn out to be missing, you can't do much more than checking for obvious shorts on either rail that may be bringing the supply down (any dipped tantalum capacitors in sight?), inspecting electrolytics for obvious bloating (or high ESR if you have the means), and checking rectifier diodes for shorts. If you do need to check switching transistors or other parts on the primary side, make sure the unit is unplugged and the main filter capacitor has been discharged to a safe voltage level. These things are no joke.
I was unable to find a service manual for this unit, but apparently the power supply section is shared with the DC-1, for which you can find one on HiFiEngine, and I'm assuming the general architecture won't be entirely different. Notably, that one derives its DAC +VA from +5VD, and there's an additional pair of +/-5VA to power a bunch of PGAs which are being derived from +/-15 V. So definitely start there.
No details are being provided on the mains power supply side so I suspect it is a SMPS module sourced externally. If you have no prior experience working on these, go watch some videos on SMPS repair, keep your distance from the primary side, and if +/-15 V turn out to be missing, you can't do much more than checking for obvious shorts on either rail that may be bringing the supply down (any dipped tantalum capacitors in sight?), inspecting electrolytics for obvious bloating (or high ESR if you have the means), and checking rectifier diodes for shorts. If you do need to check switching transistors or other parts on the primary side, make sure the unit is unplugged and the main filter capacitor has been discharged to a safe voltage level. These things are no joke.