Report #2 - outdoors ground operation
It works brilliant for data - 1.1kbyte/sec data rate and no worse latency than GPRS. It is installed as a 19200 baud generic modem and this data rate is about equiv. to 9600.
I tried it with and without the £25/year Onspeed data compression proxy service which saves a lot of money on GPRS/3G but this test is dial-up with no data volume charge. The data compression should still increase the data rate but I find that Onspeed have taken on so many users that their servers are loaded and there are significant delays which, while still saving the money on data volume billed services such as GPRS or 3G, seem to cancel out on dial-up access.
I used
Primex Internet "free" (PAYG) dialup. One can dial their 0845 # from abroad - essential in this case. 0044 845 ...
9600 is easily fast enough for most airborne data requirements, not including dirty movies
Next... vehicle and airborne. The last one will have to wait till Tuesday (no hangar access at weekends).