User's Manual

9
3.2. Power Supply
Power amplifier is using one 3 KVA toroidal transformer. A soft start is provided using relays and
resistors (placed on the switch-ON board). The high voltage is made by combining 4 x 575V AC
(total abt. 3200V DC) @ 1.2A. Each has its own rectifier and filter. In the high voltage circuit, safety
resistors are employed to protect the amplifier against overload (placed on the power supply board).
The separated supply for screen grid is regulated by stabilization with MOSFET and delivers abt.
330V DC at 100mA. Control grid voltage is also stabilized (-120V DC). Change of stabilized first
grid voltage is controlled by the software (EBS for example).
Primary section of the transformer is adjustable for 230 - 250 VAC. Factory setting is
240VAC. If the AC voltage in your network is 230 or 250 Volts, you need to set the correct
value before first starting of the PA. See part 7.1. for more information. Other primary
voltage is possible on request (for example 200V 50/60 Hz for Japan).
3.3. Safety Devices
Control and monitoring circuits ensure control and safety during malfunctions of the PA. These are
placed on the Control board, which is located on the chassis subpanel.
One of the important safety element is mechanical
switch for AC blocking at opened amplifier.
4. INSTALLATION
Read this chapter carefully prior you will start installation. Before unpacking inspect
shipping carton first, if it is not damaged. Keep all of packing parts for possible future
shipment. Check unpacked power amplifier. If you find some damaging, contact your
dealer immediately to keep full warranty.
During installation go step by step according to the next parts.
Type of supported TCVR and working
frequency are visible on the display.
AUTO LED is ON.