Quick Troubleshooting Guide
Amp won't turn on
1. Make sure that the AC mains cord is securely connected at both ends.
2. Verify the power source with something that you know works (a radio, a light, etc.).
3. Check the Mains Fuse, and replace it if necessary (if it blows again, refer your amp to
qualified service personnel).
There's no sound
1. Make sure that the guitar cord to the input is okay (wiggle it--check your guitar's volume
setting, too).
2. Check the Volume controls.
3. Check the Standby switch.
4. If an effect or signal processor is plugged into the Effects Loop, make sure it's turned on
and that the level controls on the amp and processor are set correctly.
5. Check the speaker cable or cables to see if they are disconnected or shorted.
6. Check for blown speakers.
7. If a fuse is blown, replace it (if it blows again, refer your amp to qualified service
personnel).
The amp shuts down unexpectedly
1. Follow the seven steps in the "There's no sound" section.
2. Turn off the amp and wait 25 minutes before turning it on again. An internal thermal
protection circuit can shut the amp down if it becomes overheated.
3. After 25 minutes, turn it on, and if it shuts down again, refer the amp to qualified service
personnel.
Note: On SEMKO 230/250-volt models, there are two additional T 1.6A (250-volt Slo-Blo
type, 5mm x 20mm) fuses and one T 10A (250-volt Slo-Blo type, 5mm x 20mm) fuse
located internally. These protect the amp's output tube filaments and should only be
replaced by qualified service personnel.
There's unwanted distortion
1. Check the speaker(s).
