Sergei Bezrukov writes:
In this project we send and receive digital data by using a 433MHz transmitter and receiver modules TXM-433 and RXM-433 manufactured by LINX. We also use LINX helical whip-style antennas. The following images show the first part of the project – assembling the modules on a PCB and establishing RF connection between them.
Transmitting digital data over RF with LINX modules - [Link]