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User Manual
Rev. 1.0 - 29/11/12
TEX30/50/100/150/300LCD
ELETTRONICA
7.1.2.3 Driver section
Before passing to the final power amplifier, the RF signal is preamplified in this
section by an ERA3 transistor. When the exciter is placed on stand-by, the driver
is by-passed.
7.1.3 Telemetry board
This board is designed to inform the user of the equipment operation state. All
input and output signals are available on the DB15 connector.
The same board also features the “INTERLOCK” BNC connector for disabling the
device. By grounding the central pin, the output power is reduced to zero until the
connection is removed.
When an R.V.R. amplifier is used, this connector is linked to the power amplifier
REMOTE or INTERLOCK by means of a BNC-BNC connection. In case of amplifier
faults, the central conductor is grounded thus forcing the machine to enter in
stand-by mode.
7.2 TEX30LCD Different Parts
7.2.1 Power Supply
The
TEX30LCD
power supply unit is a switching-type unit whose +28 V main output
powers the machineÌs RF amplifier. The power supply also features stabilizers for
generating cont5 V and +18 V voltages for supplying the other equipment
circuits. Note that the power supply is a “direct from mains” type, or rather it is
without a transformer, and it can be connected to any voltage between 80 and
260 V without any adjustments or manual settings. The power supply unit is also
connected to 24 V auxiliary continuous voltage inputs used to automatically buffer
the mains power cutoff.
7.2.2 Power Amplifier
The final power stage is enclosed in a totally shielded metal container fastened
in the centre of the device.
The RF signal coming from the “main” card reaches the pilot, is amplified and is
then sent to the final stage that sees to its final amplifications up to 30W.
The amplifier is made in three stages. The first is made with one BFG35, the
secondwith three BFG35 in parallel, and the last with one BLF245.
In addition to the actual RF amplification, this circuit carries out the following
functions:
