I've been using one of those cheap digital storage oscilloscopes (Protek DSO-2090) that plugs into your computer's USB port. I think maybe I'm beginning to see one of the downsides of this type of device. Either that or my circuit is really messed up--that's what I'd like to find out!
If I measure two signals around 7mhz using the two channels I have available, does the phase angle between the two signals that I see on the screen represent what's actually going on in my circuit? Or just some variable latency in the connection between the scope and my PC?
With the differential amplifier I'm testing right now I can see that the phase angle between the two outputs is around 180 degrees on average, but it varies wildly--so much so that at some moments the two outputs are nearly in phase. I'm not sure if that is what's really happening in the circuit.
Thanks a lot!