Hi, I am working on a basic curve tracer circuit for use with my oscilloscope and I have some questions I hope to get help with. I am trying to keep it basic, using jelly bean parts I have on hand and optionally running it from a battery. Here is where I am so far.
I am generating a 6V peak to peak 1 Khz triangle wave with the bottom peak touching ground, then running it through a 1k resistor which both limits current and allows current to be measured. This is working and I can see curves for diodes and the oval for some capacitors, however only small capacitors work. Larger capacitors and all the inductors I have on hand to test show as a short circuit (which makes sense to me given the frequency and current limit). A really rough schematic is attached. It contains options for removing the DC offset and also going to 12V peak to peak, but I have not tried these options yet. It works from 7.5 up to 16, so if running on higher voltage, a 12V trangle wave should be easy to achieve. The op amps are speced for 30 ma max output. The 1k output resistor keeps things well under this.
It seems to me that this would be much more versatile if I had selectable frequency and/or output resistances. I am building this just because it seemed interesting - I don't yet have any specific use in mind for this device. So, the question is: What other frequency and/or output resistances would be good to have?. And, a follow up to this is how to size capacitor C6 for removing DC offset when these things can be changed.
I'd like to add a step generator at some point too, but I haven't started looking at this yet.
Any other traps for "rookie" players that I should look for?
Thanks