Please, excuse my poor English.
I have a DSO112 that sometimes after power it on the input just showed a maximum negative signal, independent of scale. After some fiddling, it worked again as normal.
But now it’s doing permanently, always negative both on AC and DC coupling but about cero on GND.
I’ve tried to download the schematics on http://www.jyetech.com/forum/viewtopic.php?f=17&t=358, but it seems the files have been corrupted. Anyway, I have opened the oscilloscope to diagnose it.
And to my surprise, there is a negative voltage of about -3.6V on the solid state relay before the connector.
In fact, if I select DC coupling I can measure the same on the crocodiles.
Any ideas of what is happening? Is there an alternate download for the schematics?
Thanks in advance.
