Correction: If you anlötet a 17cm long wire with 'ANT', the part works smoothly, also from the next room. A brochure was not apparent from this, however, stands on the Amazon HP in the product description.
Now the transmitter switched my sockets of a Raspberry Pi controlled, for the receiver I have no use yet. At this price you may have to accept a few compromises, prospective buyers are now so hopefully informed.