Loop antenna outdoor unit connectors: Two M6 stainless steel threaded studs and BNC female (RF out 50 ohms) Supply current (head unit fed with 13.8 V from bias-tee): 100 mA Supply current (head unit fed with 5 V from bias-tee ): 25 mA Supply voltage (head unit): 4.5 to 15V from a bias-tee feed via the coaxial cable Gain (head and base units Loop Antenna Amplifier ++): 25 dB at 14 MHz This is ideal for fixed station operations with high quality loops and high performance base station receivers or transceivers.įrequency range (Loop Antenna Amplifier ++): 5 kHz to 150 MHz
Vlf receiver amplifier full#
Using our bias tee unit allows the antenna amplifier to work over it's full range. The components in the internal bias tee inside a SDRPlay receiver limits the minimum frequency to 500 kHz. The Bias Tee unit is intended for use with a 12 V feed which allows the head unit amplifier to have a greater dynamic range than with the 5 V available from a SDRPlay receiver. The photograph on the right shows the prototype with a 1m diameter loop of LDF4-50 coax cable as a test loop. We supply a 3m (10 ft) length of wire as a simple loop to make a first loop for testing. We have tested it with simple wire loops or deltas, coax loops and an alloy loop made from a bicycle wheel rim. The loop depends on what the user has available. Like our other active antenna products it has RF overload protection to allow it to be used very close to transmit antennas without damaging the amplifier or the attached receiver. The bias tee unit is a PCB with two BNC connectors and a DC socket to take DC power from a battery or power supply. The outdoor unit is housed in a polycarbonate box with stainless steel antenna connections and a BNC socket. The head unit can also be used on it's own powered by the internal bias tee inside a SDRPlay receiver. The amplifier consists of two units, a weatherproofed outdoor head unit for connection to a suitable loop and a bias tee unit to provide DC power up the coaxial cable to the outdoor unit. The Loop Antenna Amplifier ++ contains all the electronics needed for home DIY construction of an active loop (magnetic loop) low noise receiving antenna.