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 Previous: Youth@HamRadio.Fun: K2BSA--A Huge Success! |  Next: ARRL Helps to Clear the Air in Line Noise Cases |
 Al Ward, W5LUA, and his dish. |
NEWINGTON, CT, Aug 20, 2001--Here's another one for the Amateur Radio record books. On Saturday, August 18, hams in Texas and Manitoba completed the first 24-GHz Earth-Moon-Earth (EME) QSO. The contact followed by several months the first documented echoes from the moon on 24 GHz.
Noted microwave enthusiast Al Ward, W5LUA, of Allen, Texas (EM13), says his QSO with Barry Malowanchuk, VE4MA, in Winnipeg, Manitoba (EN19), was a result of several years of effort in trying to optimize antenna gain and receiver sensitivity, and to obtain adequate power to make the roughly half-million mile path to the moon and back.
 Barry Malowanchuk, VE4MA, and his 24-GHz dish. |
"Signals were weak but easily copied at both ends," Ward said. The August 18 QSO took place at 1417 UTC on 24,192 MHz. Malowanchuk said the two exchanged "M" reports. "Signals were quite good with slightly less that the normal buzz experienced at 10 GHz," he said. The weather at VE4MA was reported to be clear and cool while W5LUA was reporting cloudy, warm and humid conditions--the cloud's and the moon's proximity to the sun making optical tracking impossible.
After many failed attempts, Ward succeeded last March in hearing 24 GHz EME echoes and documenting them for the first time. He had predicted then that an EME QSO on 24 GHz would succeed. Such accomplishments on 24 GHz are particularly significant because water-vapor absorption of signals peaks at around 24 GHz.
 VE4MA at the helm in his well-equipped station. |
VE4MA used a 2.8-meter offset-fed dish with a 1.6 dB noise figure low noise amplifier. Power is obtained from a Varian travelling wave tube amplifier producing 70 W (he reports 2 dB of loss in the waveguide to the feed horn).
W5LUA has a 3-meter prime focus dish and a 1.75 dB noise figure low noise amplifier. His Thompson TWT amp produces 80 W at the dish feed horn. A fixture in the VHF-UHF and microwave standings, Ward was the recipient of the 2000 ARRL Microwave Development Award.
Ward says that Jim Vogler, WA7CJO, in Arizona, and Lars Karlsson, AA6IW, in California, are nearing completion of their 24-GHz EME stations, and he expects QSOs with those stations soon. "Other stations in Europe such as CT1DMK and G3WDG are known to be capable of receiving EME signals," he said. "Additional 24-GHz EME tests are being scheduled for September."
QST's "The World Above 50 MHz" Editor Emil Pocock, W3EP, was among those offering words of congratulation to W5LUA and VE4MA on their accomplishment. "I know it was a long, hard road," he said.
Additional details are on the North Texas Microwave Society Web site.
| Previous: Youth@HamRadio.Fun: K2BSA--A Huge Success! | Next: ARRL Helps to Clear the Air in Line Noise Cases |
