In 1" Multi Down-Converter - RF Central RFX-RMR Operator's Manual

7.2

"3 in 1" Multi Down-converter

This board is mounted onto the motherboard as shown in the picture in section 4
The first part of the "3 in 1" multi down-converter accepts 630MHz at its input and converts this to
70MHz. The second part amplifies the 70MHz, applies AGC (automatic gain control), and passes this
signal to the final part which down-converts the signal to 4.57MHz.
A balanced form of the 4.57MHz IF is then passed to the COFDM demodulator board as detailed in
section 7.3
The module contains a 20MHz reference oscillator to lock the two mixer local oscillators.
There are no user serviceable parts on this module. Please contact RF Central Service Department
for maintenance of this unit
BP filter
630MHz from
st
1 downconverter
BP filter
RFX-RMR
Mixer 70MHz BP filter
780MHz
PLL/LO
REF
OSC.
65.43MHz
PLL/LO
RMR RX
3 in 1 Multi down-converter Down-converter
Issue 1.0
70MHz
AGC
detector
4.57MHz balanced
baseband to
demodulator
page 18 of
To analog RX
and IF monitor
41