Hi Bill!
Why didn't the dual-817 guys buy an 847?
My reasons for the dual-817 setup.
1. They had been discontinued at the time I decided to try SSB satellites in 2008, and I didn't want to pay the relatively high price to get a used 847 at that time.
2. I already had one FT-817ND since this version came on the market in 2004 (replacing an non-ND 817 I bought in 2001), and tried other receivers for a portable full-duplex all-mode satellite station. After several months and minimal success, I bought a second FT-817ND. The larger - and smooth-spinning - VFO knob, compared to the other receivers I tried, was a big selling point for adding the second 817 over using other radios. This is what I still use today, although on some occasions the receive 817 will be replaced by other radios (Kenwood TH-F6A, laptop with FUNcube Dongle Pro+, and previously an Icom IC-R20).
3. The 817s can be a self-contained setup, running on their own internal battery packs. Not being able to have a home station, something self-contained (or powered from an external 12V source) was necessary.
4. Should I decide to go with computer control, the 817s have Yaesu CAT ports.
I really like being able to pack my portable station (except for the Elk log periodic antenna, and anything that isn't OK in a carry-on bag for air travel) in an old laptop bag. I had this with me in Hartford for the ARRL Centennial Convention in July when I met you, although I don't remember if you saw any of my demonstrations. This station has gone with me for all of my trips I've taken - by ground, or air - since going to Dayton in 2010. Even to Australia in 2011.
If I can rig it up this weekend, I will set up a camera to record a pass where I use the two 817s, with a closeup of the radios. Maybe this will help show how I've been working SSB satellites for the past few years.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/