Friday, July 31, 2015

Simple Ham Radio Antennas--HF Active Loop Antenna | Southgate Amateur Radio News. Post #504.

HF Active Loop Antenna | Southgate Amateur Radio News: This page is brought to
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Source:  http://www.southgatearc.org/news/2015/july/hr_active_loop_antenna.htm.



Page last updated on: Thursday, July 30, 2015
HF Active Loop Antenna.

Cross Country Wireless have released a HF Active Loop Antenna with a frequency range of 200 kHz to 70 MHz with extended coverage up to 148 MHz.

The antenna can be for all LF, MW and HF professional monitoring and short wave listening. It can also be used for VHF FM reception and will give useful VHF airband reception when mounted outdoors.

The antenna is a triangular loop antenna 1.3m (51") wide with a built-in low noise high dynamic range RF amplifier. A base unit allows 12V power to be fed up an ethernet cable feeder to the antenna. The antenna current consumption is 150 mA. The base unit also has a two way splitter to provide two separate RF outputs.

Local RF noise rejection of the antenna allows it to be used indoors with good results where outdoor installation is prohibited. In addition to the excellent local noise rejection properties of the loop antenna, transformer isolation, common mode chokes and the balanced pairs in the ethernet cable help keep RF noise away from the antenna element.

The antenna is built from fibre glass and stainless steel with a polycarbonate box housing the amplifier. For outdoor installation a mounting bracket allows it to be mounted to a 50mm (2") pole using a clamp fitting or a 25mm (1") using a Stauff clamp for mounting on Clark Mast or Hilomast telescopic masts.

The antenna can be quickly assembled and disassembled to allow portable operation from temporary listening sites with compact storage and easy installation in areas with restricted access.

BNC female connectors are used for the RF output ports on the base unit. RF over-power protection on the antenna and the RF outputs allow the antenna to be used very close (>2m) to transmit antennas and tolerate accidental connection of a transmitter to the RF output sockets for a short period (150W for 30 seconds) without damage. The antenna could be mounted on top of a rotatable HF beam as a low noise diversity reception antenna.

The antenna is supplied with 20m of ethernet cable and a mounting kit with fittings for mounting on 50mm (2") or 25mm (1") diameter masts.

The antenna is now in production.

http://www.crosscountrywireless.net/
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Comment:

This antenna seems to perform quite well, despite its small size.  The bandwidth is narrow, but that's a small price to pay for versatility.  This antenna can be used in deed-restricted areas, for portable operations, and for emergency communications.  Various mounting configurations can used, from ground mounting to the apex of a HF beam antenna as "a low noise diversity reception antenna."  For the latest Amateur Radio news and events, please check out the blog sidebars.  These news feeds are updated daily.  You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed.  Thanks for joining us today!  Aloha es 73 de Russ (KH6JRM).