Simple Passive Component V-I Curve Tracer

RE: Simple Passive Component V-I Curve Tracer

beacon_dave — Sun, 01 May 2022 18:17:55 GMT

Another nice post.

FYI you have a slight typo on the scope model number though:
"...My oscilloscope is a Keysight DS)X1102G..."

Some viewers may be confused by your 3V peak-to-peak voltage comments as the scope waveform appears to be showing 6Vpp ( although you do mention that the generator is in 50Ω output mode ). Would the Hi-Z output setting perhaps be more appropriate here as I've seen it used in the Keysight training materials ?

RE: Simple Passive Component V-I Curve Tracer

dougw — Sun, 01 May 2022 17:12:46 GMT

Very interesting.

Suppose you used the junction between the DUT and the resistor as your scope ground and inverted the current probe signal, would your scope be able to handle that? Would you need an isolated function generator for that scenario?

RE: Simple Passive Component V-I Curve Tracer

shabaz — Sun, 01 May 2022 10:35:04 GMT

Hi Frank,

Nice video and explanation!

Also, nice lighting, shadows were at a minimum, I struggle with that.

The same circuit and equipment can also be used as an impedance meter. One option to solve the voltage on X point that you mention, is to find a transformer and use that to isolate the function generator. Then, the ground of the 'scope probes can be put in the middle junction of the DUT and resistor, i.e. Y connected to the bottom of the circuit instead. The transformer method has its own limitations however, since then you can only test within a certain frequency range.

Great experiment it provides so much insight into a range of components and networks.

RE: Simple Passive Component V-I Curve Tracer

Andrew J — Sun, 01 May 2022 09:18:30 GMT

I thought the quality was good. In fact, I actually thought the embedded video was from W2AEW and I spent some minutes scratching my head working out why your comment made no sense!! Great post.

RE: Simple Passive Component V-I Curve Tracer

fmilburn — Sun, 01 May 2022 04:02:02 GMT

The real reason for this post is that I've decided my videos aren't that good so I've downloaded ShotCut, an open-source video editing program, and I am learning to use it. This is my first attempt. There are pops at the start of the inserted audio - I think I need to let it run a bit before starting to talk and then edit that out. I'm pretty sure the problem is the software. If not that, then it must be the camera and I need to buy a new one. It can't be me :-)