The cause of the "Crazy Source" problem seems to be the following: - The power supply board is attached to the top control surface. - The voltage regulators are mounted to the back wall of the synth. - The sockets connecting these voltage regulators to the power supply board are at located the "hinge point". Every time the control surface is pressed, it moves the power supply board. Since the regulator pins and sockets corrode over time, this movement causes intermittent fluctuations in load resistance thus causing voltage drops. This inturn causes grief for the CPU and logic circuitry. Note: Moog had issued technical bulletins on how to resolve this problem through the use of special plastic regulator holders however these parts are not necessary. The easy way to repair the problem is to essentially desolder and remove the troublesome sockets and "extend" the voltage regulator leads through the now empty socket's through-holes. Resistor leads or 20 to 22 awg wire make great "extensions". Simply push the "extensions" through the pc board's through-holes and solder these to the legs of the corresponding regulators. Since the regulators are attached to the big aluminum block, soldering is easy and there is no need to remove the regulators. Steps: 1. Open synth. (with power off and UNPLUGGED!!) 2. Unplug all connectors to the power supply board (note their position and orientation) 3. Remove two screws holding the power supply board to synth's control surface 4. Remove two screws holding the power supply board and aluminum heat sink assembly to the synth's back panel 5. Remove the power supply board and aluminum heat sink assembly from the synth (watch out for the messy heat sink compound!!) 6. Desolder all regulator sockets. 7. Unscrew two screws holding the power supply board to aluminum heat sink. 8. Remove the regulator sockets from the power supply circuit board. 9. Reassemble the power supply board and aluminum heat sink assembly. 10. Push wire or lead through each of the socket's through-holes and solder to the voltage regulator leads. Do one at a time. Don't solder leads to circuit board yet. 11. When all leads are soldered, inspect for poor joints, shorts, solder balls and solder bridges. 12. Solder "extended" leads to circuit board solder pads. 13. When all leads are soldered, inspect for poor joints, shorts and solder bridges. 13. Install the power supply board assembly in the synth then reassemble synth. Note: The aluminum heat sink has lots of heat sink paste on it. This is very messy stuff. You may wish to put wax paper or a plastic bag on the work surface. If you get mixed up with the connectors P-13...P-16 They are labeled. Simply match the label to the silk screened text on the circuit board. All edge black wires for each connector are on the right hand side. (Missing pins on the sockect match missing wires on the connector)
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