I've worked Mode A on AO7 with an 817 and had similar results. I added a 30 watt amplifier and it was enough.
My suggestions are to add an amp and (if possible) upgrade your antenna to a yagi, at least 5 elements.
BTW, I've got an RF Concepts RFC 2-23 available for sale... 2 watts in, 30 out, with built-in pre-amp. I don't have my 817 anymore so this is surplus to me.
73 de N8AU, Jim in Raymore, MO
Light travels faster than sound... This is why some people appear bright until you hear them speak.
Date: Thu, 13 Sep 2007 13:35:47 -0400 From: "tjjapha@earthlink.net" tjjapha@earthlink.net Subject: [amsat-bb] AO7 Info for kb2hsh To: amsat-bb@amsat.org Message-ID: 380-220079413173547221@earthlink.net Content-Type: text/plain; charset=US-ASCII
You may have hit the nail on the head. I don't do Mode A, but that's what I found on Mode B. 5watts just didn't hack it (small antennas at even a great portable QTH) on Mode B. That was uniformly the case for me at a number of QTHs. I added a 20 watt amp. and it works great. The 817 was used in all cases. Nobody says I'm too strong with the 20 watts!
Good luck, Tony, N2U