I apologize if this is in the wrong sub-forum, but…
I have a tektronix 2215a scope, and I built the curve tracer thinking I should be okay if I were to enclose it in a metal enclosure, with x/y outputs to the scope. But, All I am getting on my scope is a horizontal line!
I AM correct that the curve tracer should work in this application… right? If I am correct, how should I set the scope up?
NOT MY PICTURE! Just a picture of the same model of oscilloscope that I have for reference
@ke8uyv-shawn to setup the scope you need to have switched to XY mode in which your CH1 (input) becomes X axis and CH2 (input) becomes the Y axes. Do it from The SEC/DIV knob. Page 2-5 in the instructions manual. Regarding the Horizontal line is OK. That’s what you should see (just a horizontal line (when your curve tracer circuit is IDLE so you’re not probing/measuring anything). But the minute you short the probes (together) you should see a Vertical line instead. Let go of the probes and the horizontal line should return. I suggest that you watch again the relevant videos on Patreon. It is all there. You just have to pay attention “Closely”.
@ke8uyv-shawn Just make sure you’ve aligned the curve tracer first (before use) by “strictly” following the described procedure {see VIDEO 26 (Build a Curve Tracer Board) begin @11:24 Time-Stamp}
Well…
went back to make sure the curve tracer was correctly aligned last weekend, and my scope had developed an issue of no traces. May have found some direction in finding the problem. I’ll go ahead and order new caps this weekend and hopefully get it operational again.
I have a question about this project and the oscillator.
It looks like in the previous video a 1 kHz signal was selected for the oscillator in this project.
However, that frequency is going to be fundamental to the curve tracer operation. Why 1 kHz? Might it be useful to add in switchable options to have different ranges to test? Has anyone experimented with different ranges – and for what purpose??
I can imagine that Pico farad capacitors, and perhaps really fast switching transistors are going to require higher frequency input – but how high are we thinking here?? Has anyone experimented with this,
Paul – any insight?
Cheers!
@badandy If you are a contributing member on Mr. Carlson’s Patreon page you will see (by watching his videos in relation to this project) that he has already mentioned the possibility to use a mechanical switch or similar and different value caps in the RC network should you choose to use different frequencies for different applications. PS: 1KHz is also useful as a nice low distortion injection frequency for when you want to text or repair audio equipment.
@ovi4 yes I’m a Patreon member – might have missed that in the video (but I do recall a switch he repurposed on that old scope)…
More curious if anyone has tried other frequencies and what worked. Mindful that higher frequencies are going to need more gain. And I think the Wein Bridge tops out at around 100kHz