Since I have decided that the local telco here (SBC) is charging way too much, I don't like the idea of just having a cell phone for my home line as it's not very convenient (and won't work for DirecTivo!), T-mobile's "family plan" is a pretty good deal ($10/mo/additional phone), and Vonage is reportedly okay, but more expensive than option 2 (and I'm a cheapskate), I decided to get ahold of a Telular SX5e GSM fixed wireless terminal.
Overall, I'm fairly pleased with the SX5e; it does what I need, and does it well (and cheaply). The only problem I have encountered was getting my DirecTivo units to dial out over it. The SX5e comes with a book, complete with codes to change various aspects of calls. There is one in particular, "#*19*2#" that causes the SX5e to 'proxy' a modem call. It's actually pretty slick, when in this mode, the SX5e initiates a 'GSM data call' (or so that is how the bill shows it), and then initiates a connection from itself to the calling device, proxying the data applying error correction and such (as chosen by the previously mentioned codes).
The problem I had with just adding "#*19*2#," to the dialing prefix on the DirecTivo was that after a few minutes, it would disconnect, and complain that the remote had hung up. Some calls worked, but some didn't, and code updates surely didn't. Mainly, the SX5e is designed for least-cost routing from a PBX, or a remote office; basically the modem connect feature is designed for credit card POS terminals. So, after muking with various prefix codes on the DirecTivo (",034#", ",019#" and the like) without much success, I decided to try some of the SX5e's settings. I happened to find out that the "Air Interface Data Rates and Error Correction" settings needed to be tweaked a bit. After plenty of test calls, I found that "#*115*1*7#" was the string that was needed. This means the dialing prefix is "#*19*2#,#*115*1*7#,". Pretty crazy, but it works like a champ... The "#*19*2#" for modem bypass, "," for a pause (maybe not needed, but I like to be safe), "#*115" for "air interface data rate set", "*1" for "error correction on", "*7#" for v.32/9600bps, and the last "," for the last pause.
Originally, a problem I had encountered was that the DirecTV call was failing. The DirecTivo makes two calls (despite what the brilliant DTV support staff thinks), one to the Tivo service (for sending thumbs up/down/usage reports/code updates), which is done via the "local" number you set up on the Tivo, and another call to DirecTV, which is a toll free number, apparently utilizing the dial prefix/etc. to send PPV data to DTV. Why this call failed was beyond me. I'd think if any call would have failed, the Tivo one would have, but...
Speaking of brilliant DTV support staff, I tried to get them to help me with this issue by not telling them I had this SX5e. They, of course, asked me to navigate to the 'last call status', which was "Successful". They were stumped, and dumped me up to "level 2 support". They still had no idea the thing was making two seperate calls, and everyone to whom I spoke I had to explain "THE THING MAKES TWO CALLS... CALL "A", THE TIVO CALL, SUCCEEDS, CALL "B", THE DTV CALL FAILS."... Unfortunately for me, I happened to have a power outage at the very moment I was speaking to them, and lost my status in "level 2 support"... At this point, I was on the phone for 2 hours or so, so I gave up.
It used to be that I could not leave the phone line plugged in constantly as the thing would keep trying to call DTV, and a bunch of 1-2 minute calls on my bill added up and quickly exceed my monthly minutes (4 sets of 2 calls/day/1-2 minutes/call, you figure it out, oh and 'toll free' calls do count towards your monthly minutes). So, I had to plug it in every month or so. Not too bad, since the thing gets its guide data over the satellite anyway. Maybe I should have left it plugged in... What does a toll free number cost the CALLED party again? Of course the only reason I want it plugged in is to send my "thumbs" data up. Maybe they will cancel the horrible "reality" shows like Nanny 911 and crap*. (*riiight)
Like I said, that was in the past. I think it is now working correctly, as I haven't seen a plethora of 1-2 minute calls to the toll-free DTV number since I changed to the 9600 baud rate. It works and I don't even notice - that is what I want.
OH, and by the way... If your DirecTivo (series 2) doesn't get to call out at least once every month or so, it will get slower and slower. Then, when you try to dial out, it will NOT WORK. I had this happen to two units I had. Luckily, they were under warranty, and were replaced as such. I'm not sure the specific reason, but it locks on "Negotiating" during the dialing sequence... DTV had no idea (suprise), and a full system reset didn't even work (clearing all data).