Hi Bernhard!
I'm looking for a suitable antenna that I can use to operate over AO-7 in mode A . The main requirement that it be hand-held.
Other than what KA3HSW suggested, the closest thing to a handheld 10m antenna may be a whip of some sort. Or possibly go with some sort of wire antenna. Still not truly handheld, but a small antenna for 10m will make hearing the downlink a tough exercise.
During the past summer, I took out my Buddipole dipole and its 8-foot mast and tripod to work with AO-7 in mode A. I settled on an L configuration, where the horizontal part of the antenna pointed toward the satellite. I would move the antenna every minute or so, and held my Elk antenna toward the satellite for the 2m uplink. That worked OK, but not great. I could easily hear my 5W CW signals from an FT-817ND through the mode A transponder. It was much harder when I went to SSB at the same power level. I made one mode A SSB QSO with W7JPI, and that was hard work. Now that I have a back yard to work from, coupled with the end of the summer heat here in Arizona, I may revisit that over the next few months.
Good luck, and 73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/