Operation Manual Part 2

Digital Liquid Cooled UHF
TV Equipment
Description / Test points / Location of units
9946 V1
45321648.01 104 A E
preliminary
80 / 131
Numéro / Number Doc. Rev. Lan
g
u.
16/06/2006
Pa
g
e
Information contained is this document is confidential, is THOMSON property and cannot be disclosed in whatever form without prior written authorization of THOMSON.
3.10. The power amplifier, 45323629
3.10.1. Outline
The power amplifier is designed to amplify
residual sideband modulated television analogue
signals for all standards, and digital signals in
DTV.
It is designed to work in UHF transmitters for 650
to 750 MHz.
The power output specification is as follows :
♦ vision :
• approximately 2100W peak power at 1 dB
compression,
• 960W rms power with a gain of 63 dB,
♦ vision plus sound :
• approximately 2100W peak power,
♦ peak power of 2100 W, for 570 W RMS
approximately with digital signals.
3.10.2. Architecture
The power amplifier consists of the following sub-units :
♦ protection card and interface,
♦ class A preamplifier,
♦ class AB drive amplifier,
♦ input splitter, 1 x 8 ways,
♦ final class AB 2100 W amplifier consisting of eight amplifier modules,
♦ 4 way combiner,
♦ power supply distribution card,
Figure below shows the positions of the various cards in the power amplifier.