SDG #280 Micsig STO1004 Portable 4 Channel 100 MHz Oscilloscope

The Micsig STO1004 sits in an awkward but interesting price bracket: too expensive to be an impulse purchase against entry level benchtop oscilloscopes, but justified by what it includes. Four channels at 100 MHz, 1 GSa/s, 70 Mpts of memory, an 8 inch 800x600 touchscreen, 32 GB of internal storage and a battery that returned a genuine five hours plus in testing. The notable omission is segmented memory, which is worth knowing for anyone capturing bursty signals.

The review works methodically through the interface rather than listing specifications, and the criticisms are specific. Menu discovery is the main learning curve: the trigger button does not open the trigger menu, so either the menu key or the swipe down gesture must be used. Adjusting the trigger level is also clumsier than it should be, since dragging anywhere on screen moves the whole waveform rather than the level marker. Fine vertical positioning does not snap cleanly to round values either.

On the positive side, pressing the timebase encoder brings up a quick list of timebases, which makes moving between a rolling 1 second view and 100 microseconds fast. Measurements taken from the displayed waveform are supplemented by a proper hardware counter, which stays locked while the screen based frequency reading wanders. Maths covers the usual arithmetic, FFT, ax+b and a user defined expression evaluated in real time.

Serial decoding is exercised properly with a live UART feed, including the tabular text view that captures packets that cannot be resolved on the waveform. CAN decoding plus the battery and HDMI output make a strong case for in vehicle diagnostics. The one real complaint is weight: one handed use tires quickly, and a neck strap would help.