Intercontinental Technologies Ltd F22-6D Manual Do Utilizador

Page 39 of 87 

This Chapter provides an overview of the major functions of the F22 Series, including a description 
of the transmitter, the receiver, and the major parts of each. 

 
The most important components of the transmitter are the Encoder/Button printed circuit board, the 
RF Module, and an EEPROM. 

 
12.1.1 Encoder/Button PCB 
This module is the heart of the transmitter.  It contains the pushbuttons, power 
control circuitry, micro-controller, and EEPROM (see Figure 8).  The micro-
controller encodes the information from the pushbuttons, along 
with security code and error correction data, into a serial data 
stream.  This data stream, after passing through an audio-
frequency-shift-keying circuit, is sent to the transmitter RF 
module. 
 
12.1.2 Transmitter RF Module 
This module is a narrowband FM transmitter with a digitally 
synthesized frequency output using a phase locked loop circuit 
(see Figure 9). 
 
12.1.3 EEPROM 
This component, found on both the Encoder/Button PCB and 
Receiver/Decoder Module, contains all of the programming and 
security code information used by the micro-controller.  It is a 
non-volatile memory device, meaning that it does not require 
constant supply of power to hold its contents.