EI/DL1YMK - EME DX pedition

August 2005

This is picture collection which I got from Michael DL1YMK. Very soon will be here more information about EI EME DX pedition and log with QSOs. Thanks to Michael was possible to work with EI - DXCC during his holiday in August 2005. Appreciation help bring to the pedition also his wife Monica, which was helping him to build and operating dish in very strong windy weather in EI.

Words of Michael:

The EI/DL1YMK Moon-bounce Story 

As first skeds were scheduled by Joe, K1RQG, for the 21^st of August, I immediately began to set up the 4.1 m stressed dish with Monika's helping hand after we had arrived at our holiday home in IO41TU in the afternoon of the 20.08.2005. In fact, we were ready to go on the 21^st around noontime. As the fridge had to be loaded, we left for a short shopping trip, leaving the dish in a bird bath position, as the wind was breezing up a little. Unfortunately, when we came back, the wind had turned to gale force and we found the dish sprouts for one half of the dish’s circum-sphere to be bent over to almost 180° - a horrible sight for me... Now the dish really deserved it’s nickname: mud (mighty ugly dish)...

 Sad enough, I wrote an email to Joe in order to cancel all skeds, he had arranged. We both were very much disenchanted, however, it was only for Monika’s persistence that she urged me to find a repair solution for this bunch of scrapped aluminum tubing. During the first week, we had ongoing gales moving in from the Atlantic, no way to tie the mesh panels onto the sprouts, which in the meantime I provisionally had re-bent to something they had looked like before. For the 27^th, the sea-weather forecast indicated moderate wind-speeds force 3-4 for some hours and the ‘small craft warning’ for the fishing boats was suspended the first time since some days. This was our chance, maybe the only one we would get.

 On the 26^th in the evening we therefore prepared the dish in about  2 hrs time and informed Joe that we would try to be on. When the Moon came into our range, we made the first echo test at around 02:00 UTC on the 27^th. In fact, we heard weak echoes, although the dish was swaying up and down in the wind due to rotator backlash. At around 02:15 UTC we suddenly heard a very strong signal tuning on 1296.045 MHz. It was F2TU, we immediately called him and made a QSO 559/549. Obviously, the system worked and we subsequently made 13 complete contacts during that activity period.

 The Moon wasn’t set already, when the storm came up very quickly again and we had to remove the 18 panels in a hurry. Impatiently, we had to wait until the 29^th of August late afternoon for the gales to calm down a little. Now, with sufficient practice we quickly moved the mesh back in and sent out the word via K1RQG that we would be on the Moon for a second try early Tuesday, 30^th, which of course was a normal working day...

Echoes were better than during the first attempt, but for stability reasons the dish still was under-illuminated (we had to move the septum feed into the dish in order to provide at least some balance). In the very early morning we started to work ON7UN, who we knew had to leave for work, but Eddy made it right in time for work – and I assume – he was quite happy that day...Nine other stations were to follow during the next hours, not bad for a Tuesday, isn’t it ?

At 15:10 UT, just before our Moonset, we heard HB9JAW calling us, but failed to make a QSO, as Michel later told us he had problems with the tracking computer.

 In only about 20 hours of operation time with winds low enough to keep the dish on the Moon, we made 23 contacts with a significant number of ‘firsts ever’( will have to follow up). Certainly we would have loved to be on for a longer period and to work a few more of the lunatics gang, but inevitably the storm was giving the rules...

 The RIG we used consisted of a modified IC910 H (to give 15 W on 23 cm with a clean signal) with 500Hz filter, a 3-stage homebrew preamp (MGF4919G, Filter, ATF10136, Filter, MSA0804) with overall N/F=0.35 dB @ 43 dB gain, a solid state 500W LDMOSFET HPA from DB6NT, all driven by a homebrew sequencer. Antenna auto track was performed by F1EHN software with a 10 bit-EA4TX-interface. The septum feed used was produced by Zdenek, OK1DFC. The reflector is fully collapsable and has an f/D = 0.45, which is unusually deep for a stressed dish, but works fine, if you pay attention to some important details, like tensile dissipation along the sprouts.

 This DX-pedition to EI was a very first test, entirely dedicated to portable Moon-bounce  for 23cm, with a setup capable of running random QSO’s in CW. Certainly, there will be  more to follow, as the EI-activation was big fun, despite all the troubles we ran into. We learned a lot about all the things, which will have to be widely improved until next summer. There are plans to also integrate 70 cm into the feed system for the next DX-pedition in 2006...so where do we go next ?

First install of tripod and ribs, very nice dish portable construction
First half is o.k.	Monica	Parking position	Equipments
DFC Septum feed horn made by OK1DFC		PC work	Booming to Moon
CQ via Moon	View over the dish	Dish front of house	Detail of feed
EME DX pedition crew	Monica installing mesh		Michael DL1YMK