© Christoph Petermann DF9CY 2010

Last Revision: 25 April 2010

A summary of the event

I do not have a EME system today, only a tropo antenna without elevation possibility on 70cm (2 x 9 ele stacked). At first I thought, do some listening with it and that's it. I had planned to attend a local astronomy weekend at the same weekend and two weeks before I thought it might be a good idea to show EME at that meeting place. So I took out a spare 10 element antenna - not a good one. Simulations show only 11 dBi of gain. But something should have been possible. I have a good preamp (0.6dB NF and 20dB gain) and my IC820H TRX. A tripod from one of my astronomical telescopes and a mount from a satellite dish, which needed to have an additional hole to be mounted on the tripod. Voila, the antenna was then attached to this and it looked almost "professional ...".

On April 16th I set up the system for the first session at Arecibo. Beside this I had the video stream from Arecibo running in my shack and I was aware that there was only low power. During the SSB session one could have the impression, that sometimes there was someone talking - a bit low in frequency. But once having switched to CW there it was exactly on the same frequency. I could copy KP4AO ca 80% of a transmission. I thought if this is possible with low power a high power operation should give a 100% copy.

I took the whole stuff to the astronomy meeting. The first place on the site I found between all the telescopes was bad due to a lot of birdies from the telescope controllers. So I moved and I had a very good place at the entry of the site, where everyone would pass along. So I had a whole busy afternoon explaining what was going to happen here. At 1900 local time I gave a lecture - that room was well filled with about 50 listeners - and we went out at 1940 and immediately heard KP4AO in SSB with good quality. We realized the break, when the PA was changed and then followed the event. Many people came along and were astonished about the SSB readability of the signals. We had 80 to 100% copy all the time. Later in when in CW it was a 100% readability. After the event I took the chance and - we had a clear sky - I went observing the sky through many of the telescopes on that site.

On sunday evening home again I could not resist and switched 70cm on. I was astonished to receive KP4AO in CW with the moon 30 degrees offset with the two vertically stacked antennas and no preamp (which in fact is blown up by a nearby lightning strike in last December). When KP4AO switched to JT65B I could decode almost every sequence.

Thanks again to you,Joe K1JT and all others that made this KP4AO event happen. It was a great pleasure.

More Images of the Aschberg - EME Event

WSJT screenshots of KP4AO

Antenna was 25 degrees out of direction with missing ca 8 .. 10 dB of gain.

YouTube Video of Setup

16 April 2010: 432 MHz Arecibo KP4AO - DF9CY testing receiver setup. See the dramatic sky in the background from the Icelandic volcano ash. KP4AO is very barely audible . The have been transmitting with low power only.