Operations Manual

DESCRIPTION 2-4
O&M of the MCC-545B PACKET DATA RADIO
12/2000
2.6.1 MCC-545B Transceiver Assembly
The receiver assembly contains a complete 4K baud Bi Phase Shift Key (BPSK) receiver, a
transmit and receive frequency synthesizer module, and a 4K baud BPSK modulator.
BPSK Receiver
! Input band pass filter (37-50 MHz)
! RF amplifier (17 dB)
! Low pass image filter (Fc=50 MHz)
! Mixer
! IF amplifiers and filters (10.7 MHz)
! Noise blanker
! Mixer, 2
nd
IF filter and amplifier (100 KHz), and RSSI circuit
! Coherent Costas Carrier Tracking Loop
! BPSK bit detector and clock generator
Synthesizer (1
st
and 2
nd
local oscillator and transmit oscillator)
! Reference Oscillator (12.8 MHz +/- 2.5 PPM)
! Tx phase lock loop ( 74-100 MHz output, 20 KHz steps)
! A divide by 2 circuit (37-50 MHz output, 10 KHz steps)
! Rx 1
st
local oscillator phase lock loop (47.7-60.7 MHz output, 10 KHz steps)
! Rx 2
nd
local oscillator phase lock loop (10.6 MHz)
! PIC Microcontroller
BPSK Modulator
1. I/Q Vector Phase Modulator (BPSK)
2. Pre amplifier (+13 DBM output)
All components are located on a 8.5”by 3.5” two sided printed circuit board. All components are
soldered in (surface mounted). As an option the board can be conformal-coated with an acrylic
encapsulate that contains a tropicalizing, anti-fungal agent to increase durability and provide
protection against moisture and contamination.