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This is an example of a basic remote control design utilizing Holtek

encoder/decoder IC available from Linx.

When a key is pressed at the

transmitter, a corresponding pin at the receiver goes high.This basic circuit can

be easily modified to suit a broad range of applications, and demonstrates the

ease of using and interfacing the Linx modules.

Notes:

1)

DIP Switch used to set ID code. A 4-position switch was chosen for this example but

all or none of the 8 address bits (A0-A7) may be used.Settings of the Receiver and

Transmitter must match for signal to be recognized.

2)

VT (valid transmission) pin goes high when incoming signal is recognized and

matched.

3)

These outputs will go high as the corresponding buttons are pushed at the

transmitter. They can be interfaced directly with a microprocessor or used to turn on

and off LED’s, buzzers, etc., (Holtek chips can only sink/source 1mA on output pins

so external components may require a driving transistor.)

Figure 10: Basic Wireless Encoder circuit

Figure 11: Basic Wireless Decoder circuit

BASIC REMOTE CONTROL EXAMPLE