Wireless monitoring systems are currently a common part of both industrial and domestic solutions. In case of industrial use, it may be a sensory system at a point where it is not possible to implement a fixed line, or it is necessary to repeatedly change the position, respectively, the location of the measuring probes. This is, in particular, the monitoring of environmental parameters (temperature, humidity) in bulk materials, biomass, or agricultural crops in storage facilities. For domestic use, local weather devices and systems are part of smart households such as lock control (entrance gate, apartment entrance), light control, and HVAC control. Devices that utilize wireless technology for communication include IoT devices as well. This article describes the use of the VirtualWire communication protocol using radio frequency waves with a carrier frequency of 433MHz-900MHz. The main topic of the article is the design and implementation of a secure one-way communication channel. Such a solution consists of a transmitting device with implemented desired sensors and a receiving device that aggregates data from multiple transmitters.