RF / IR Encoder / Decoder Chipset

RF600E

RF Evaluation Boards,

RF600D

HiRK decoder area.

AM-HiRK-433 receiver/decoder module.

(M5)

Learn switch.

(SW2)

Learn LED.

(LED7)

Data LED’s.

(LED8, 9, 10)

Power supply area.

5 volt regulator.

(U5)

Supply indicator

(LED11)

The radio keyfob is a standard R. F. Solutions AM-110C3-433 keyfob which contains an RF600E encoder

chip and also an AM radio transmitter circuit. Three push buttons allow the user to send commands to the

RFEVAL2 board where the signals will be received and decoded.

The RFEVAL2 board is supplied with a circuit diagram and also a parts list and can be used for a wide

range of development tasks including the following.

Remote switching - software and hardware systems can be simply prototyped and tested.

Range and environment testing - these initial stages of project design can be carried out and valuable

results obtained without the expense of PCB design and procurement.

Solve the great AM/FM question - the low cost of AM modules must be balanced with their lower

performance when compared to FM and accurate comparisons of performance can be carried out with this

board.

Aerial test - the transmitter board has provision for both AM and FM modules and can be fitted with helical

stub and 1/4 wave whip aerials, thus allowing module and aerial performance to be tested and optimised.

RF Input Circuit.

The RF input stage of the RFEVAL2 board can be implemented using either a radio receiver module or

alternately using the composite hybrid receiver / decoder HiRK module.

The can accept up to 3 radio modules and each module has an associated pair of option links. One of

these couples the +5 volt supply to the module and the other allows for the connection of the ‘data out’

signal to the decoder IC. The need for a +5 volt option link may not be immediately apparent but most

radio receivers are in practice transmitters as well and radiate from their local oscillator stage. If these

signals are picked up by a nearby receiver then they may well cause distortion of incoming ‘real’ signals or

in extreme cases my completely prevent operation of the receiver. The four modules which may be fitted

to the board are as follows.

FM-RRFQ1 FM module (M3) which receives signals from a compatible FM transmitter module such as the

FM-RTFQ1. Operation is possible at data rates up to 4.8Kbps and at distances up to 250 metres over

open ground.

AM-HRR3 AM module (M4) which receives signals from a compatible AM transmitter module such as the

AM-RT4 or AM-RT5. These modules will operate at up to 4 Kbps and over a range of up to 500 metres.

The super-regenerative circuit used, results in a low cost device with adequate performance for many

short range applications. Note that this module position will accept RRS3 modules which utilise a superhet

circuit to give improved performance and range over the HRR3 devices.

Irrespective of how many modules are fitted, it will be necessary to connect the +5 volt and data lines of

one module using the link options filed on the PCB. It is important that only one pair of links be made at

DS600-9 Sept ‘04

©2004 Reg. No. 227 4001, ENGLAND

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