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6.2.
Fuse Replacement
The user is allowed to change mains fuses (6.3 x 32mm), accessible from the rear panel, only. In the case
of fuse (fuses) interruption inside the power amplifier,
exchange can be carried out only by professionally
qualified persons!
Internal fuses are located mainly on the SWITCH-on board (next to the HV
transformer).
One special fuse, filled with sand, is used in the model
OM2501HF(OM3501HF). In the case of an accidental discharges or
short within the tube this fuse (4 Amps fast, filled with sand) saves
the HV supply circuits.
Fuse F 4A
6.3.
Tube Replacement
In the case of a damaged vacuum tube , contact the manufacturer or your dealer for ordering a new one.
We will provide instructuions for replacing the tube.
Replacement should be done by a professionally
qualified person!
After tube replacement the
automatic BIAS adjustment
procedure must be done.
6.4.
Cleaning
To prevent damage to the amplifier surface and plastic components, do not use aggressive chemicals for
cleaning. Do not open the amplifier for cleaning. Outer surface cleaning may be safely accomplished by
using a piece of soft cotton cloth moistured with clean water or window cleaner.
7.
APPENDIX
7.1.
Primary AC voltage selection
Primary section of the HV transformer is switchable for three values of AC voltage (220, 230, 240V)
Factory settings is 230VAC. Before first starting the PA we recommend checking that the correct value is
selected according to the AC voltage in your network.
Type of supported TCVR and working
frequency are visible on the display.
AUTO LED is ON.
