Saturday, April 17, 2010

EME Experiment to Hear KP4AO from Arecibo

This weekend a group of hams were operating EME (Moonbounce) using the 1,000 foot diameter radio telescope at Arecibo, Puerto Rico. They used the call KP4AO. I decided to try and see if we could hear and maybe work them using a single yagi. So, we set up the antenna in a make-shift manner on the patio and proceeded to point it at the moon and listen during the time KP4AO was on the air. We were able to monitor a real-time computer link of the operation and compare it with what we heard. KP4AO made 103 QSO's in about 2-1/2 hours of operation. We copied their SSB signal quite well at times but usually it was pretty much in the noise. When they finally shifted to CW, we were able to hear them very well. We were not able to make a QSO with our kludged together station but we gave it a good try.

Below you can see the K1FO 25-element yagi we used for the Arecibo, Puerto Rico, EME experiment today. The yagi is supported by a mostly fiberglass stepladder and secured to it by a rubber strap and dacron line at the base. The rear of the antenna is supported and raised above the concrete patio by a cardboard box. In the second photo you can see the "manual" method of antenna positioning. As long as we could see the moon, it worked well. But, with the moon so close to the sun today, only a very tiny sliver of a crescent was visible and that could not always be seen. In the photo on the right, you can see our "Target" in the upper right-hand portion of the image. You need to look really close to see it. In this photo the moon had moved away from where we were pointed and a re-positioning needed to be done. (You can click on any photo for a larger image then use your browser's BACK button to return to this page.)

Below are a couple of photos of myself, W8TN, and Rick, W8ZT, operating the station. Rick brought an Icom IC-706 and a 150-watt amplifier. You can see the Bird wattmeter on the chair between us in the first photo. Feedlines were REALLY short so we had essentially no loss to consider.

Hal, W8HC, was the photographer so we have no shots of him but he also spent a good deal of time on the mike and on the key trying for a contact. What a hoot it would have been to hear his call come back from the moon! Maybe next time.

1 comment:

AB0WW said...

Nice job and nice site. K6IV and I made a 20-element 432 MHz antenna with a wood boom and welding rods for elements, but were unable to hear Arecibo on Saturday 17 April, in Pleasanton CA. AB0WW.