Betso Sharkie Wideband UHF Active Antenna

Compact and wideband, the Betso Sharkie is a log periodic dipole array for UHF reception, with a cardioid pattern and a built-in low-noise amplifier.

The amplifier’s gain is set from −9 to +18 dB in 1 dB steps. Turned up, it makes up the loss of a long coaxial run; at zero or negative gain on a short cable with a strong signal, it keeps the receiver’s input from overloading. Its noise figure is under 0.75 dB, its IP3 over 34 dBm, and its VSWR under 1.2.

Input filters cut signals below 450 MHz and above 870 MHz, such as those from walkie-talkies, FM radio, wireless focus systems, Wi-Fi, Bluetooth, and mobile phones, so the wireless system sees fewer dropouts.

A seven-segment LED shows the gain at power-up and can stay on. Its brightness follows the ambient light or holds a fixed level. The display can also be turned off while the amplifier keeps working, and a press of any button wakes it. The antenna is powered through the coaxial cable from 5 to 20 V DC and draws about 35 mA.

The antenna element is glass-reinforced epoxy laminate, and the amplifier housing is CNC-milled aluminum, sealed against water. It mounts on a stand or boom pole with its 1/4 in and 3/8 in threads, and the Betso Sharkie Nylon Pouch protects it in transport.

Features

• Wideband 470 to 850 MHz log periodic antenna with a cardioid pattern
• Low-noise amplifier with gain from −9 to +18 dB in 1 dB steps
• Noise figure under 0.75 dB and IP3 over 34 dBm
• Input filters against out-of-band signals
• Gain display with automatic, fixed, or off brightness
• Powered through the coax, 5 to 20 V DC
• Water-sealed aluminum amplifier housing
• 1/4 in and 3/8 in mounting threads