Model 501

Most communicators are well aware of the problems associated with “close-in” HF communications. Frequently it is easier to raise a station 2,000 km away than one’s base of operations 100 miles distant. To a large extent, the problems of short-range communications are related to inadequate antenna performance. Traditional antenna performance suffers from one or more of the following limitations:

• Inadequate bandwidth and efficiency. No short­range broadband antenna before the 501 covered the most important lower frequencies down to 2 MHz with adequate efficiency.

• Improper pattern. Vertically polarised radiators do not support the skywave.

The performance of the Model 501 is tailored for the short-range and close-in sectoral coverage applications. The 501 radiates a broad, upwardly directed beam, slightly biased in one direction. Thus, it serves well for broad sectoral coverage and for short-range point-to-point.