Does anybody know if 3G aircards work even where there is no 3G phone service? Finding any solid info on aircards seems to be impossible....

My guess is that Air Cards are depended of 3G and if there is no 3G available I guess they will fall back to EDGE.

My guess is that Air Cards are depended of 3G and if there is no 3G available I guess they will fall back to EDGE.

That's my guess too, but I was hoping it worked differently. Right now I can tether my iPhone to my laptop, so I guess I have no use for an aircard. I live on an island with shoddy internet, so I'm trying to find a backup connection other than EDGE if the broadband goes out.

Aircards are really 3G and/or EDGE cards...that is, if a 3G signal is presence they will use that...if no 3G signal they will fallback to using EDGE. During the late 2011 floods I used an AIS 3.6Mb 3G/Edge Aircard along with a month's worth of unlimited 3G/EDGE service...the aircrad worked fine but unfortunately the place I evacuated there was no 3G coverage; only EDGE...averaged around a 200Kb download speed.

Aircards are really 3G and/or EDGE cards...that is, if a 3G signal is presence they will use that...if no 3G signal they will fallback to using EDGE. During the late 2011 floods I used an AIS 3.6Mb 3G/Edge Aircard along with a month's worth of unlimited 3G/EDGE service...the aircrad worked fine but unfortunately the place I evacuated there was no 3G coverage; only EDGE...averaged around a 200Kb download speed.

Wait, your EDGE connection was getting 200kb download speeds? That sounds like 3G speeds to me? The EDGE connection on my phone gets about 8 kb...

Aircards are really 3G and/or EDGE cards...that is, if a 3G signal is presence they will use that...if no 3G signal they will fallback to using EDGE. During the late 2011 floods I used an AIS 3.6Mb 3G/Edge Aircard along with a month's worth of unlimited 3G/EDGE service...the aircrad worked fine but unfortunately the place I evacuated there was no 3G coverage; only EDGE...averaged around a 200Kb download speed.

Wait, your EDGE connection was getting 200kb download speeds? That sounds like 3G speeds to me? The EDGE connection on my phone gets about 8 kb...

You might be confusing Kilo-bits per second and Kilo-Bytes per second?

The theoretical maximum EDGE speed is, I think, 236.8 Kilo-bits per second (Kbps) downstream, or ~ 30 Kilo-Bytes per second (KBps). 200 Kbps is probably the maximum real-world download speed when accounting for overhead and other inefficiencies in packet-based communications. Most people have reported ~ 150 - 180 Kbps EDGE here. GPRS max. is (I think) ~ 80 Kbps.

For the OP, every/any 3G aircard will almost certainly support quad-band GSM data: 850/900/1800/1900MHz for 2G-GPRS/EDGE in addition to any 3G frequencies specced. When not receiving a 3G signal the aircard will fall back to EDGE/GPRS, assuming that is available.