Marshall® DSL100    Discharging the Filter Caps

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To discharge the power supply filter caps, first find R71.  It's the "sand block" resistor marked with red tape in this photo.  (The circuit board might say R63 instead of R71.)

This resistor connects the two large power supply filter caps (they're the tall black cylinders).  You want to "bleed" charge from each end of R71.

Do this with a 5 or 10 ohm, 5 or 10 watt resistor.  Jumper one end of the bleed resistor to the amp's metal chassis.

Jumper the other end of the bleed resistor to one end of R71 (the metal ends are found underneath the sand block).

Leave this clip lead connected for about 10 seconds, then switch it to the other end of R71 for another 10 seconds.

Dropping Resistor