The PA 2522 should be connected to the 50 Ω input of a spectrum analyzer or oscilloscope. The preamplifier is powered by the power adapter, which is included in the case. The PA 2522 can be used, for example, to amplify the measurement signals of the Langer near-field probes. To achieve this, a near-field probe with a suitable frequency range and corresponding cable should be connected to the input of the preamplifier.