The yellow waveform line on my DSO138 is stuck on the bottom line of the screen. It flickers at different rates as you'd expect when I change the timebase and turns into a solid line if you press Hold but no waveform is shown whatever you put on the probe, and trying to change the vertical position has no effect. It looks like the output of the ADC is stuck at zero.
Any ideas how I can fix it? For example, can I reflash the firmware?
Waveform stuck at bottom of screen
Re: Waveform stuck at bottom of screen
OK, now sorted. When I started measuring voltages it became apparent that my adjustable output power supply was set to 6V only. I did a 0V line alignment but this only messed it up for when I switched my power supply to 9V. Another 0V line alignment fixed it but I still had to hold the + button for several seconds to get the vertical position indicator off the bottom line.
(Maybe this reply will help anyone else hitting the same problem.)
(Maybe this reply will help anyone else hitting the same problem.)