NXR-800H
19
The D/A converters (IC701 and IC802) converts the AGC
setting (D_PC) of the driver circuit and control voltage value
(PWR_CONT, PWR_PRT) of the Final Unit (X45-386 A/5).
The A/D converter (IC803) converts the transmitter unit
(X56-312 A/3) temperature, VCO & VCXO control voltage
(CVT, CVT-REF and CVT-MOD), Final Unit (X45-386 A/5) PA
current (PA_CURR), fan current (FAN_CURR), detection volt-
age (FWD_PWR, RFL_PWR), etc.
The shift register (IC703) controls each part of the trans-
mitter unit (X56-312 A/3) based on serial data of the Control
Unit (X53-413).
3. Final unit
The RF final amplifier unit (X45-386 A/5) amplifies the
transmitter power to a specifi ed level.
This unit consists of the following circuits:
(1) Transmitter power module
(2) High pass fi lter
(3) Forward/Refl ect power detector circuit
(4) Antenna switch
(5) Harmonic fi lter circuit
(6) APC circuit
(7) High temperature detector circuit
(8) FAN action control circuit
(9) Current detector circuit
(10) AVR Circuit
(11) Other Circuits
3-1. Transmitter power module
The power module IC10 uses power module RA30H4047
M123 (C) or RA45H4047M131 (C2) to improve its effi ciency.
The driver output of the transmitter unit passes through an
attenuator and enters the power module IC10 pin 1. Power
module IC10 amplifi es the RF power according to the volt-
age at the amplifi cation control pin 2 (VGG) and outputs it
through pin 4 (Pout).
3-2. High pass fi lter
The T type single stage high pass fi lter prevents the Pow-
er Amplifi er Module from being broken by static electricity.
3-3. Forward/Refl ect power detector circuit
The forward / Refl ect power detector circuit consists of a
CM coupling type detection circuit formed by a Micro strip
line and the differential amplifi er IC4.
A part of the transmitter power is detected by diodes D9
and D10 and is converted into DC voltage.
CIRCUIT DESCRIPTION /
电路说明
D / A 转 换 器 ( I C701 和 I C802) 转 换 驱 动 电 路 的 A G C 设
置 ( D _ P C ) 和末级单元 ( X45-386 A /5) 的控制电压值 ( P W R _
CONT,PWR_PRT)。
A/D 转换器 (IC803) 转换发射机单元 (X56-312 A/3) 温度、
VCO & VCXO 控制电压 (CVT、CVT-REF 和 CVT-MOD)、末级单元
(X45-386 A/5)PA 电流 (PA_CURR)、风扇电流 (FAN_CURR)、检
测电压 (FWD_PWR、RFL_PWR) 等。
移位寄存器 ( I C703) 根据控制单元 ( X53-413) 的串行数据
控制发射机单元 (X56-312 A/3) 的各个部分。
3. 末级单元
RF 末级放大器单元 (X45-386 A/5) 将发射机功率放大到指
定电平。
该单元由以下电路组成 :
(1) 发射机功率模块
(2) 高通滤波器
(3) 前向 / 反射功率检测器电路
(4) 天线开关
(5) 谐波滤波器电路
(6)APC 电路
(7) 高温检测器电路
(8)FAN 动作控制电路
(9) 电流检测器电路
(10)AVR 电路
(11) 其它电路
3-1. 发射机功率模块
功率模块 IC10 用 RA30H4047M123(C) 或 RA45H4047M131(C2)
的功率模块提高其效率。发射机单元的驱动器输出通过衰减
器并进入功率模块 IC10 针脚 1。功率模块 IC10 根据放大控制
针脚 2(VGG) 的电压放大 RF 功率，将其从针脚 4(Pout) 输出。
3-2. 高通滤波器
T 型单级高通滤波器可防止功率放大器模块受到静电损坏。
3-3. 前向 / 反射功率检测器电路
前向 / 反射功率检测器电路由微带线形成的 C M 耦合式检测
电路和差分放大器 IC4 组成。
发射机功率的一部分被二极管 D9 和 D10 检测并转换为 D C
电压。
Fig. 9 Transmitter power module /
图 9 发射机功率模块
RA30H4047M123 (C)
RA45H4047M131 (C2)
:
Pin
@
VGG
.
VDD
;
Pout
Summary of Contents for NXR-800H
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