One thing I found disappointing with the HPS140 is the lack of any automatic time-based measurements. I appreciate that accuracy is limited by the use of the processor’s on-chip RC oscillator, although calibration should be able to get this below 1%.
The hardware is already all there, so the addition of Frequency, Period, RPM, pulsewidth and duty cycle measurements wouldn’t cost any more, but would make it so much more useful an instrument at no additional build cost.
It would also be useful if you could show these, as well as other automatic measurements in a large display format.
Pity the lack of a USB port makes firmware uprades tricky - perhaps a way round this would be to add a bootloader which reads audio-band data - you could then upgrade simply by connecting the scope to the PC sound socket…!