Sunday, 30 December 2012

G4OBK Beverage Antenna now repaired

The hedge cutting which took place in November savaged my western beverage antenna - so today I repaired it.

Feedpoint of my beverage antenna
This inexpensive long wire aerial, which is mounted beween three and five feet above ground, is fed by buried 50 ohm RG-58 coax. The feeder is then connected to a home made 9:1 ferrite balun transformer.  The 475 feet length aerial is then terminated to ground via a carbon resistor network of around 500 ohms at the opposite end to the coax feeder.

This receiving aerial is directional and favours signals in the direction of the Yorkshire Dales, Lake District and USA. In effect the aerial comes into its own between a frequency span of 500 KHz up to 7 MHz and is very effective at picking up signals in a span from South America  (215 degrees) round to Alaska (340 degrees). Use of this directional antenna allows me to listen to Manx Radio on the Isle of Man on 1368 KHz, as it nulls out the stronger signal from BBC Lincolnshire on the same frequency.

The aerial performs extremely well on the 160m band (1.8MHz) but I have also found the beverage antenna excellent for receiving DX communications on the 60m (5 MHz) band when used in conjunction with a 1/4 wave vertical antenna for transmitting. The aerial design is used commercially by government agencies.  Some radio amateurs are using 12 of these antennas covering each 30 degree point of the compass. 

Harold Beverage in his 1920s radio shack
The aerial needs to be some distance away from the transmit antenna or induction takes place. This can ruin the performance of this low noise receive antenna. 

Harold Beverage an American engineer, conceived this antenna. He died in 1999 at the age of 93. He was Chief Research Engineer for RCA in the USA from 1929 until 1940 and continued to work in the field of communications for the rest of his life.  

More information on the antennae used in my station can be found here

No comments:

Post a Comment