New Quad - flat line inputs

Just got new DSO203 :smiley: … :frowning:
Arrived with:
HW Version 2.60
DSO203 Mini DSO Sys Ver. 1.51 I upgraded to Sys 1.52
DSO203 Mini DSO App (Plus A1) Ver 1.00 I updgraded to APP 2.53

Yesterday, I had the wave generator output connected to Ch A ok. Signal looked good.
(10x probe connected to Wave Out and 1x probe connected to Ch A and both probes connected together.)

Today, I cannot get any response on Ch A or Ch B from the wave generator or an external 1.8 Vpp signal.

I have reloaded the firmware, re-formated the USB drive to eliminate the parameter not loading error.

Forum search indicated possible damage to D6 or an op amp, but that was only related to bad waveform generator output.
I’ll open the dso to look for possible damage as soon as I have some time.

Any suggestions what this could be or possible remedies? Are there any input settings that could cause this?


The probe connectors are sometimes a bit unreliable; make sure they are really connected. If you are using the hook on the probe ends, make sure that it is also firmly in place.

To make sure, you could touch a wire directly to the connector on the DSO, to make sure the fault is not in the probe.