Road King Manual - Mesa Boogie

REAR PANEL CONTROLS & FEATURES (Continued)FUSE:This is the A.C.’s (Alternating Current) main fuse and provides protection from outside A .C. fluctuations as well as power tube failuredamage. Should the FUSE blow, replace it with the same rating in a Slo-Blo type package. The domestic U.S. version requires a 4amp Slo-Blo fuse. A power tube short or failure is often the cause of a blown fuse...Follow the cold start procedurementioned in the Hi Volts switch section and watch the power tubes as you flip the Hi Volts to the ON position. If aBOLD SPONGYpower tube is going bad or is arcing you will see it! Flip the Hi Volts switch down immediately and replace the faultypower tube and the FUSE if necessary.POWER FUSE120 V~ 4 A60 Hz SLO4 A BLOFUSEIf you see nothing abnormal as you lift the Hi Volts switch, it is possible that a power tube shorted temporarily and blewthe FUSE. If this is the case it may work again normally. To be safe, you might want to replace just the adjacent tube orall power tubes in the “shotgun” troubleshooting tradition and save the replaced set as spares. Spare fuses are a mustfor the fabled cord bag along with your spare tubes. Always carry both for they could be worth their weight in goldsomeday.PAGE 28