Sorry if my english is a little bad.
I own a Picoscope 5442A and I have a question about probes affecting the circuit. This is probably easy for you too understand and I wonder what it is I am doing wrong.
The test circuit is as following.
When I add probe 3(P3) the LED turns off so I can't measure the voltage over the phototransitor.
I have added a video showing the problem.
Sorry if this is a stupid question, but what is it I am doing wrong?
I bought it primarily since it had 4 channels and had PC connectivity as I like to record my findings.