Fall 2009 Issue

Amateur Radio and
the Cosmos
Part 2 – Crawford Hill


In part 1 of this series WA2VVA began his exploration of the curious connection between amateur radio and the cosmos. In this segment he continues his exploration, this time going as far back as the dawn of time.

By Mark Morrison, WA2VVA

Photo 1. This NASA photo shows the Crawford Hill site as it appeared in 1959.

Traveling along New Jersey’s Garden State Parkway, just north of the Holmdel exit, is an area of great significance to cosmologists and VHF enthusiasts alike. Rising gently from the roadway, and hidden from view just beyond the trees, is a modest geological feature known simply as Crawford Hill, the highest point in Monmouth County. In the 1930s it was here that Karl Jansky first detected radio emissions from outer space. In the 1940s it was here that George Southworth, who joined the ARRL in 1915, developed his so-called “waveguide technique,” including transmission lines, filters, and electromagnetic horns, all descendents of his waveguide invention. Horn antennas would become an integral part of AT&T’s microwave repeater system, with their distinctive burnt-orange colors dotting the towers across America. The brooks and streams in this area still bear witness to an ancient time, with bones and teeth of prehistoric animals still being found there. However, in the 20th century Crawford Hill would bear witness to an even older age, the dawn of time itself.

In 1959, when AT&T learned of NASA’s plans to launch a metallized balloon for studies of the upper atmosphere, its potential as a microwave relay system was quickly recognized. John R. Pierce, a colleague of George Southworth, convinced AT&T to enter into a joint venture with NASA. Bell Labs would develop the communications equipment and NASA would provide the launch hardware. The program, known as Project Echo, would involve three ground stations: the JPL station at Goldstone, California, the Naval Research Laboratory station at Stump Neck, Maryland, and the Bell Labs station at Crawford Hill in Holmdel, New Jersey.
The Holmdel site would employ two antennas, a 60-foot Kennedy-type dish used for transmitting and a scaled-up version of the microwave repeater horn receiving at 2.4 GHz. The NASA photo, photo 1, shows the Crawford Hill site as it appeared in 1959.

The unique construction of the “Holm-del horn” was such that it minimized ground noise entering the main feed system, an essential requirement for detecting the extremely weak signals reflected off the Echo satellite. On the receiving side, a cooled maser was used to obtain maximum amplification with minimal noise. The tracking radar included a special receiver designed by Bell Labs engineer M.Uenohara, as illustrated in photo 2. Note the parametric amplifier in the middle of the photo.

The earliest tests of the Echo project involved vertical launches from Wallops Island, Virginia, intended to verify major systems operation prior to attempting Earth orbit. The first such launch, Operation Shotput, was held on October 28, 1959 and reported in the November 1959 issue of QST (photo 3).

Although the balloon ruptured into thousands of tiny pieces, making it visible all the way to Canada, no mention was made of this in the press, even in QST, due to public-relations concerns. Rather, QST reported the success of several VHF enthusiasts as their signals were heard up and down the East Coast. Although no two-way QSOs were reported, the amateurs who successfully bounced their signals off this prototype satellite became the first in history to communicate via such means, thus underscoring the great amateur tradition of using whatever means available to extend the reach of their signals. Although two such satellites would eventually be placed into orbit, tracking them with a good-size amateur antenna was considered impractical. Thus it was that amateurs set their sights on another passive satellite, the moon.

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