FPA-26

The Frankonia FPA-26 is a low-noise, low-power millimeter-wave preamplifier with a nominal frequency range of 18 GHz to 26.5 GHz and a usable range of 12 GHz to 28 GHz, designed to increase system sensitivity for field strength measurements and general attenuation characterization at Ka-band frequencies. With a typical gain of 33 dB (±2 dB), a minimum gain of 30 dB, and a noise figure of 3.5 dB, it compensates for the significant cable and path losses encountered above 18 GHz where even short cable runs can introduce several dB of attenuation.

Key specifications include a maximum input power of -20 dBm (87 dBµV), a typical SWR of less than 2, and 50 Ω SMA female connectors at both input and output. The housing is equipped with a 3/8″ female camera thread for mounting to a mast such as the Frankonia FSM-1.6, with the antenna itself secured via a second 3/8″ screw at the amplifier base. Polarization switching can be achieved in 45° steps using indexing bolts, making horizontal-to-vertical polarization changes quick and repeatable during chamber measurements.

A 0.5 m SMA-to-SMA coaxial cable is supplied for connecting the antenna to the amplifier input. To avoid persistent damage to the microwave cable, it is strongly recommended to orient the antenna connector in the opposite direction to the amplifier RF input, allowing a wide and smooth cable bending radius. Power is supplied via 4 mm banana sockets at 12–15 VDC / 250–300 mA. The aluminum enclosure measures 210 × 100 × 60 mm and weighs 400 g. ESD precautions — discharging coaxial cables and personnel before connection — are essential at these frequencies.