The Moon
Well, last Wednesday evening was the night. The moon was near Perigee, the sun was not in the way, and my 2m amplifier came back from M2 Antenna Systems and was reinstalled.
2m Amplifier And Sequencer
I got everything hooked up and tested before the moon came up that night. Our Earth-Moon-Earth (EME) system consists of an Icom IC-9100 Transceiver and a microHAM MK2R+ for our Sound Card along with a single M2 Systems 2M18XXX Yagi Antenna (18 elements on a 36-foot boom at 112 feet), a tower mounted preamp system from M2, and M2’s EME Sequencers along with their 1.2 Kw 2m amplifier. For software, we’re using Joe Taylor’s WSJT Application and the Ham Radio Deluxe Satellite Tracking software to keep our antenna pointed at the moon.
2m EME Setup
My first test was to bounce some echoes off the moon just as it came up. With the amp on and set for its rated digital mode output of 900 watts on 2m (it will do 1.2 Kw in SSB mode), I heard my signals coming back from the moon for the first time. The moon was between North America and Europe as it came up, and I noticed several European stations were on 2m EME. After a few CQ calls using JT65B (WSJT mode for 2m EME), S52LM, Milos in Slovenia came back to me, and I successfully completed my first EME QSO on 2m! I also worked two other stations on 2m EME from Europe – DK5SO (in Germany) and UT5UAS (in Ukraine). I suspect some of these folks may have had pretty big EME stations, as their signals were very strong. Here’s a snapshot of my first QSO with S52LM:
EME QSO With WSTJ
As you can see from the snapshot, the round trip delay to the moon and back was between 2 and 2.5 seconds. S52LM’s signal was pretty strong at -23 dB (he was also using close to 1 Kw on his end). At this level, I could not hear anything audible above the noise in my receiver. The following is what the WSJT waterfall looked like:
WSJT EME QSO – Waterfall
S52LM’s signal is the lines and dots between 0 and 200. These are fairly strong signals by EME standards. The WSJT software’s performance on such weak signals is pretty amazing. (The other lines on the waterfall are weak “birdies”).
Most of the bigger EME stations use an array of long boom yagi’s, so I am pretty lucky to get this done with a single antenna and no elevation rotator. Here’s a picture of a more typical antenna system for EME (this is DK5SO, the station in Germany where I worked):
DK5SO 2m EME Antennas
At this point, I am pretty happy with the performance of our 2m weak signal system.
I heard several stations in Australia a couple of mornings ago before I had my amplifier back. I will try to work them soon. Maybe someday an EME DXCC…. (3 down, 97 to go).
Fred (AB1OC)
