The aim of this work was double-balanced mixer implementation, which will be used like laboratory equipment. This thesis deals with design of the double-balanced mixer from first theoretical principles to a practical design of a laboratory equipment. For the practical design the integrated mixer SA612 was used. Input signal to the mixer up to 500 MHz frequency can be used. For required operation external oscillator and fifth-order low pass filter were constructed. Oscillator was designed for fixed frequency 32 MHz. Fifth-order low pass filter was inserted between the mixer and the oscillator, because of filtering higher harmonics. The second aim of the work was measuring double-balanced mixer basic parameters, such as Compression Point (P-1dB) and Intercept Point (IP3). For the IP3 measurement, another one device was required. It consists of the power combiner for mixing two frequency close signals and third-order bandpass filter, which selects required frequency band. Finally, the laboratory equipment was fabricated and its real parameters were measured.