External 35dB super low-noise preamplifier (Preamplifier) UBBV-NF 35. For optimum performance when measuring weak signals in the frequency range of 1Hz - 30MHz (or 100MHz with lower gain, see graph). The UBBV NF series provides a high impedance input signal and therefore can be operated even with the antennas of the MagnoTRACKER series or other regular 50 ohm devices. The calibration data of the preamplifier are also stored in the Spectrum Analyzer Software "MCS". It provides a continuous linear gain of 35dB. The UBBV-NF can be operated via an internal battery (running time approx 3-4 hours) or via the included AC adapter. Frequency range: 1 Hz - 30 MHz Connectors: SMA (f), SMA (m) Power: 7.4 V / 800 mAh LiPo Akku pack Also available as 25dB Version (UBBV-NF-25).