Hughes & Kettner Head 100 Manual De Instrucciones página 11

Before you start swapping tubes, ask yourself these questions:
• W as the fault or failure of the tube caused by the tube itself or by a flawed
peripheral device or component, perhaps a defective speaker cable? If you don't
get to the bottom of the problem and remedy it, it may crop up again even after
you replace the tubes.
Note: In most cases, TSC will identify an over-voltage at the tube and switch
it off before the fuse blows. You can then continue using the amp (unless it's a
Switchblade TSC 50 Combo). Read section 5.2.4 to learn more. In a few cases,
for example sudden short-circuits in the tube, there's no way of preventing the
fuse from tripping.
• D id the Mains voltage fluctuate or spike while the amp was on? In all-tube
amps, over-voltage surges in the Mains net can certainly cause drop-outs. Over-
voltages are often caused by generators and faulty high-current power circuits.
• P erhaps a fuse blew even though none of the tubes is actually defective? An old
fuse, tube de-ionization or Mains voltage power surges may have triggered the
fuse.
Things to Bear in Mind When Replacing Tubes
Replacing tubes is a job best left to qualified professionals! Accordingly, the
following guidelines are addressed and apply to qualified service technicians only:
Pull the power plug on the back of SWITCHBLADE TSC and wait at least two
minutes for power to dissipate! Then remove the rear panel. With TSC, there's
no need to adjust bias, so there's no reason to remove the chassis. Now you can
carefully pull out the tubes while gently pressing down on the clamps that hold
them in place.
Caution: Tubes can remain very hot for quite some time and cause burns for
several minutes after shutting the amp down!
If you replace all tubes, make sure they all have the same ratings. The choice
of rating is up to you. If you are replacing a single tube, please read section
5.3.2. TSC adjusts the idle current in both cases, so there's no need for manual
adjustment.
Carry out hum balance basic setting: Switch the amp to CLEAN, turn
VOLUME, TREBLE and MID to the left-side stop, and turn BASS to the right-
side stop. With the help of the trimmer HUM BALANCE, look for a setting in
which the lowest humming emerges.
How to Prolong the Life of Switchblade TSC
• Never operate SWITCHBLADE TSC without connecting a load (loudspeaker)!
• Never connect speaker cabinets with an impedance that is too high or low!
• Always use high-quality, heavy-duty speaker cords that won't crimp!
• Use the STANDBY switch for short breaks!
• Avoid exposing the amp to vibrations, especially when it's powered up.
• S witch the amp off well before transporting it to allow tubes to cool off
completely.
• M ake sure all peripheral devices and connecting cords are in a state of good
repair!
• Ensure air can circulate freely around the amp's ventilation slots at all times!
• Never expose SWITCHBLADE TSC to extreme heat or cold!
• Prevent the intrusion of dust and moisture!
• A lways check peripheral gear's specs to ensure these accessories are suitable for
the amp.
• N ever connect devices with high output signal Levels to SWITCHBLADE
TSC's Input.
• N ever operate the amp with Mains power that is too high or too low. When in
doubt ask the venue's sound technician or facility engineer.
• Refrain from DIY repairs! Also have a qualified technician replace internal fuses.
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Troubleshooting
Mains connection: SWITCHBLADE TSC won't power up when you switch it on.
• I t's not getting AC power. Check the Mains cord to see if it is connected and
firmly seated.
• T he Mains fuse is defective. Ensure it is replaced with another fuse bearing the
same rating.
• T he local Mains voltage does not match SWITCHBLADE TSC's operating
voltage
Available Voltages and How to Adapt Them
SWITCHBLADE TSC ships in two
versions rated for 110/120V and
220-240V. You will find the rating
indicated on the housing above the
Mains socket. Both models offer two
operating voltages that are selected
Switchblade TSC 100 Head & Combo
using the voltage selector integrated in the Mains socket. Ensure that the Mains
voltage matches the voltage rating appearing in the voltage selector window. This
value is legible when the amp is in the standard operating position, that is, placed
right side up. The upright number indicates the currently selected voltage, and the
inverted number indicates the alternative voltage. Check also the fuse ratings to
ensure they match the ratings indicated on the rear panel.
Voltage selection and fuse replacement may be performed by experienced service
technicians only. Accordingly, the following notes are addressed exclusively to
service technicians:
• U se a small flat screwdriver to remove the voltage selector from the Mains
socket.
• If the fuse is defective, replace it with a fuse bearing the specified rating.
• T urn the voltage selector and insert it back into the port so that the desired
Mains voltage rating is legible and appears at the top left (next to the "Voltage
Setting" arrow).
SWITCHBLADE TSC is connected properly, but no sound is audible.
• The guitar's VOLUME knob is turned all the way down.
• The amp is set to STANDBY.
• The amp's MASTER knob is turned all the way down.
• The effects loop is active and set to SERIAL, but no effect device is connected.
• T he anode fuse has blown. Ensure that it is replaced with a fuse of the same rating.
• T he fuse for the tube heating tripped (the tubes don't glow). Ensure that it is
replaced with a fuse bearing the same rating.
The amp makes ringing noises when played and tends to Feedback.
• One or several tubes are microphonic. Replace the defective tube with another
of the same type. Please also read section 5.3.2 for more about this.
The sound is washed out or muddy when you switch an effects processor on.
• T he signal processor provides a wet signal that is blended with the dry or
original signal. Depending on the type of effect, the processor may be returning
a dry signal back along with wet signal, which causes phase cancellations when
mixed to the dry signal in SWITCHBLADE TSC's Parallel loop. To prevent
this, set the effects loop to SERIAL or turn the dry signal all the way down on
the signal processor.
Switchblade TSC 50 Combo
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