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 buy against entry level benchtop scopes, but justified by what it packs in. 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 if you capture bursty signals.

The review works methodically through the interface rather than just listing specs, and the criticisms are specific. Menu discovery is the main learning curve: the trigger button does not open the trigger menu, so you either use the menu key or learn the swipe down gesture. 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 pick list of timebases, which makes jumping 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 gets a proper workout with a live UART feed, including the tabular text view that captures packets you cannot resolve 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.