NXR-800
12
2-8. AVR circuit
IC104, IC603, IC704, IC705, IC706, IC807, IC808, IC809
and IC810 are AVR ICs.
Each circuit contains its own power regulator IC to main-
tain isolation between circuits.
2-9. Other circuits
In addition, IC701 is an EEPROM. The transmitter ad-
justment data adjusted for each unit is written into the EE-
PROM. If the unit is installed in another set, it is not nec-
essary to adjust it again from the beginning, but only fi ne-
tuning is necessary for each unit.
The temperature sensor (IC804) monitors the tempera-
ture of the transmitter unit (X56-312 A/3).
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 (X45-382 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 (X45-382 A/5)
PA current(PA_CURR), fan current (FAN_CURR), detection
voltage (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).
CN801
VBATT
+13.8V
IC704
IC809
SW
Ripple
filter
IC807
IC706
IC705 IC603
IC104
IC808
8V #1
8V #2
8V
9V
CN807
8V #2
OCXO
9V’
8V #1
8V #1’
5V #1
5V #2
5V #3
3.3V
IC810
3V
Fig. 8 AVR circuit
3. Final unit
The RF final amplifier unit (X45-382 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 RA13H3340
M131 to improve its efficiency. 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 voltage at the amplifi cation con-
trol pin 2 (VGG) and outputs it through pin 4 (Pout).
RA13H3340M131
a
Pin
b
VGG
c
VDD
d
Pout
Fig. 9 Transmitter power module
CIRCUIT DESCRIPTION
To Next Page
Loading...
Need help?
General