From the outside, the Telstra Pre-Paid 3G USB + Wi-Fi modem looks like any other USB modem that you may have used over the past few years. Telstra branding is a given — it's actually a ZTE MF70 with a coat of paint — but it's otherwise a standard USB modem, right down to the plastic cap that will most likely be lost if you're not careful. The microSD and SIM-card slots sit underneath a relatively brittle plastic lid that takes careful force to remove. If you do a lot of SIM swapping, it wouldn't surprise us to see this break after a relatively short span of time.
The Pre-Paid 3G USB + Wi-Fi has two key selling points. Firstly, it's inexpensive — always a plus for the pre-paid crowd — but also, it's not just a USB modem. The big catch with a standalone USB modem is that it's designed for single device usage, whereas a Wi-Fi hotspot can service multiple Wi-Fi compatible devices. It's feasible to share your connection with many modern operating systems, but this can be a fiddly process, and one that won't always work nicely. The Pre-Paid 3G USB + Wi-Fi has in-built sharing capabilities, so you can set it up as its own Wi-Fi network to share the data connection out to other devices. That can be done either via sharing as a straight USB device, or with the included AC adaptor for a tethered hotspot experience.
That's a nice ability to have, but it's tempered somewhat by the fact that it only connects to Telstra's 3G network. As Telstra has dropped prices over recent years, it's taken on a lot of 3G customers, and that means that there are a lot of customers to share its network around with. Telstra rates the average speeds for the Pre-Paid 3G USB + Wi-Fi as being in the range of 550kbps-8Mbps download and 300kbps-3Mbps upload. Once you start sharing that out, you could rather easily hit bottlenecks. To test out whether that would be the case, we had to get to testing the Pre-Paid 3G USB + Wi-Fi in real world situations.
There are a few key metrics for any mobile broadband network, but testing them is perilous stuff, simply because there's so many variables that can affect one test in one location. So we hit the road and tested seven different mobile devices across six sites to try to get a more complete picture of mobile broadband performance in two capital cities. Why capital cities and not regional zones? Partly, that's a factor of time, but also so that we could get a picture of 4G zones — and right now, Optus is concentrating mostly on capitals for its 4G — as well as the issues that congestion can introduce into a network.
We've tried to mix up our locations as much as possible, with our six sites covering a family home in Hornsby in Sydney's north (outside any 4G zone), Darling Harbour in the Sydney CBD (for an outdoors 4G test, because the 1800Mhz frequency used by 4G LTE has some in-building issues), in Glenelg Library in Adelaide (because it has thick walls and is a busy public space), in a coffee shop in Adelaide's Rundle Mall (because, again, the walls are an issue, as well as public congestion) and finally, in departure lounges at Sydney and Adelaide airports, as they're awash with travellers checking mobile devices prior to boarding their planes.