Hope Is Eternal for Low-Profile AM

Richer plans new radio photon, while CFA, EH and Kinstar proponents press on
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Richer plans new radio photon, while CFA, EH and Kinstar proponents press on

FARMINGTON, Conn. The odds of seeing the experimental crossed-field antenna approved for use in this country any time soon appear slim, especially now that the company that was leading its development in the United States plans to market a different low-profile AM antenna.

Yet developers of other, similar AM antennas hope to have more details about their test results and certification plans in time for NAB2004.

The perception that broadcasters need to lower the visual impact of antennas has coincided with more-stringent local tower ordinances limiting the height of new towers.

Advanced Antenna Technologies Inc., based in Farmington, Conn., is the successor company to Crossed Field Antennas Ltd. Businessman Robert Richer, former president of CFA Ltd., is president of the new company.

AAT is preparing to manufacture and sell the Radio Photon Antenna, which the company claims will be a simpler, smaller, more stable form of the crossed-field antenna.

According to the company's literature, "The Radio Photon Antenna is specifically designed for use by MW (medium-wave, or AM) and LW (long-wave) stations. It is compact (and) safe, requires no ground system and a minimal amount of land."

Richer declined requests for an interview and would not comment on his new company.

Hopes unrealized

A contract dispute in 2002 between Richer and one of the CFA's co-inventors, Dr. Fathi Kabbary, led to the dissolution of the CFA Ltd. partnership. Kabbary and Dr. Maurice Hately developed the CFA in the 1990s. Kabbary and Richer formed the partnership in 1999 with the intent to pursue worldwide distribution.

The development of the crossed-field antenna had intrigued broadcasters faced with stricter land use and zoning processes for building their broadcast towers.

The antenna developers claim that the CFA outperforms conventional AM arrays using shorter towers, which are typically less than 30 feet tall. They said users could enjoy reduced costs due to smaller real-estate requirements.

Construction of a CFA test antenna in Shropshire in the United Kingdom began in early 2000 with hopes developers could record enough data to gain FCC approval of the technology in the United States. The Shropshire antenna was dismantled in 2002 after numerous construction delays.

Richer told Radio World in 2002 that engineers had problems phasing the test antenna properly. CFA Ltd.'s plans called for Ben Dawson, a partner in the Hatfield and Dawson technical consulting firm, to run tests on the Shropshire CFA. Those tests never happened.

Critics of the CFA have questioned whether the design, which uses small discs and round radiating elements to create the RF signal, is an effective radiator.

According to Kabbary, CFA antennas are in use in Egypt, Italy and China. He is seeking an agreement with another company to market the CFA in the United States.

"We are looking for a well-known radio organization in the U.S.A. to do it," Kabbary said. "We hope to build the first high-power CFA in the United States soon."

Antenna manufacturer LBA Technology Inc. announced in 2000 it had secured exclusive manufacturing and marketing rights for the CFA throughout the western hemisphere. However, according to LBA President Win Donat, the company is no longer marketing the CFA.

"LBA no longer has an interest in the CFA antenna," Donat said.

Kabbary said his company, CFA International, is the only company licensed to sell CFA antennas worldwide.

"Any short antenna system with two feeders coupling two elements is definitely a CFA," he said.

Richer declined to describe AAT's Radio Photon Antenna further, citing a "major announcement" coming in the spring.

Photons at the ready

Ed De La Hunt, associate chief of the FCC's audio services division, said he was not familiar with the Radio Photon Antenna.

"We have not heard anything regarding the use of this antenna for AM broadcast."

Sources say AAT would need FCC certification to market the low-profile antenna effectively in the United States. Without certification, a licensee would have to propose using the antenna via application. The FCC typically places multiple conditions upon such uses, including full non-directional proofs of performance to establish the antenna system's minimum efficiency and non-directional characteristics.

Other antenna manufacturers have joined the race to develop a short AM antenna that meets the FCC's minimum radiating requirements.

Star-H Corp. and Kintronic Labs Inc. are partnering on a low-profile AM monopole called the Kinstar. Star-H officials say they are moving forward with plans to submit a formal report to the FCC this spring seeking the commission's certification.

Star-H officials say the Kinstar antenna provides effective levels approaching that of a conventional quarter-wave antenna.

"There is no magic or novel technology associated with the operation of the antenna," said Mike Jacobs, director of research and development for Star-H. "It's our ability to run multivariable computer optimization in the design phase that allows us to get the performance and size levels we want."

Jacobs said he was awaiting final word from Ron Rackley of duTreil, Lundin and Rackley Consulting Engineers regarding their "technical argument" before submitting the filing to the FCC.

Field-strength measurements collected from a Kinstar test site constructed near Bristol, Va., in late 2002 showed levels 98 percent as efficient as a quarter-wave antenna.

The Kinstar test antenna was 45 feet high and 105 feet in diameter over a full 120-radial ground screen and braced with wooden poles.

Kinstar developers received a special experimental license from the FCC with 250 watts on 1680 kHz at the test site. The Kinstar antenna's height will be scalable with frequency, Star-H officials said.

EH antenna update

Meanwhile, the developer of yet another small antenna design, the controversial EH antenna, is prepared to present details at NAB's Broadcast Engineering Conference in April.

The EH antenna, in the form of a vertical dipole, is shorter than a quarter-wave antenna and requires no ground radials. EH Antenna Systems President Ted Hart said the antenna could be placed on a building or free-standing tower. He met with FCC officials last fall regarding the certification process.

"We have had good conversations with (the FCC). They agree that it works, but they are not sure about my theory since it doesn't comply with classical theory," Hart said.

Hart said plans call for building an EH antenna in Williams, Ariz., after the FCC issues a construction permit, which it is expected to do later this spring.

"The FCC will require full radiation tests on the first few antennas we build before issuing blanket certification," Hart said.

His latest version of the EH antenna, called "Star," measures just eight inches in diameter and is less than 10 feet long, he said.

Hart will present details during the "Radio RF and Transmission Development" session at NAB2004 in Las Vegas.

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