When it comes to oscilloscopes, two channels are more than twice as good as one. Many small, low-priced oscilloscopes have just one channel, and engineers immediately ask for a second channel. Well, the engineers at Oscium responded with the iMSO-204, a two-channel oscilloscope for the iPad and iPhone.
Besides adding a second analog channel to the existing four digital channels, the iMSO-204 increases the sample rate over its predecessor from 12Msamples/s to 50Msamples/s/ch even when running both channels -- no interleaving. There's no increase in the 5MHz bandwidth, but the 50Msamples/s sample rate provides 10x oversampling at full bandwidth. (Oscium's online specs don't tell you that so I asked.) The iMSO-204 also has increased data memory: 1000 points/ch compared to 240 points on the one-channel model). Each digital input can also store 1000 samples on all scales.
At $399.97 -- $100 more than Oscium's one-channel model -- the iMSO-204 is a little pricey compared to other two-channel low-priced oscilloscopes
, but it's the only one that you can use with an iOS device. The others require a laptop or have a very small screen. Having used Oscium's single-channel iMSO-104 on an iPad 2, I can tell you that iPad screen makes waveforms easy to see. Even on an iPhone 4, the waveforms are clean.
When designing the iMSO-204, Oscium's engineers had to decide on the connector. Wisely, they chose to keep the 30-pin connector and not switch the Apple's Lightning connector. Doing so means that users need not replace their iOS devices just to use the iMSO-204. If you have an Apple device with the Lightning connector, you'll need the adapter, which you can order from Oscium.
Oscium has shipped an iMSO-204 for me to try. Look for a hands-on review in EDN's Test & Measurement Design Center in the near future. I'll be using an iPad 2 and an iPhone 4S. Now if I only had an iPad with a Retina display
— Martin Rowe, Senior Technical Editor