User's Manual

Table Of Contents

ATLAS 4500 Multimode Station Technical Manual May 2017 A-9

135-175 MHz Power Amplifier Appendix A - VHF Circuit Descriptions

IC4 is configured as a boost DC-DC converter and provides +25 V DC output.

IC3 regulates +5.2 V supply down to +5 VDC.

IC48 regulates +5 V supply down to +3.3 VDC.

A.3 135-175 MHz Power Amplifier

This section contains information on the following Power Amplifier components:

• Attenuator

• Driver Module

• Output Power Amp

•Power Coupler

• Power Detector

• Harmonic Filter

• PTT Power Control

• Auxiliary Circuits

A.3.1 General Description

The PA contains the following components

• Variable attenuator

• Driver module

• Main power amp

• Cooling system and heat sensor

• Coupler for DPD system.

• Power detector

• Low pass filter

• PTT switch

• Serial flash memory and regulator