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Simple Transistor Curve Tracer for Oscilloscopes.

Simple Transistor Curve Tracer for Oscilloscopes.

FREE PDF FILE AVAILABLE FOR DOWNLOAD! Link at the bottom of this text!. I know the curve is the wrong way around but simply invert your X channel to fix that.
This is a very simple Curve Tracer circuit. It's simple enough to put it up on a bread-board. It can do all sorts of semi-conductors like Transistors (Si or Ge), Diodes and you'll even get traces from a PNP transistor. It measures the Collector current as a function of the Collector/Emitter Voltage at different Base currents. You can determine the number of traces on screen by changing the ratio between C4 and C5 (change value of C4). If you make a print for this and build it onto a case you could use a multi-step switch with different capacitors so you can dial in the number of traces on screen. If you invert channel one (X) then the traces will point to the right, like you normally see with curve tracers.

On my website I've written an article about this curve tracer with some test pictures and the best scope settings for...


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Tags: transistors

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  1. Date: June 27, 2017 at 12:08

    I'll be honest ed this went over my head but it looks pretty cool what's it actually used for? Felt very relaxed watching this for some reason thumbs up x

  2. Date: August 25, 2017 at 22:25
    Author: Warren Curry

    EdEditz, this is an excellent presentation for a fully functional curve tracer. Been wanting to build one of these for a long time. Many thanks. WA9KZY

  3. Date: June 2, 2018 at 00:09
    Author: Gazza-usa

    This is a very clever circuit. The ramp generator is just beautifully elegant.

  4. Date: August 21, 2018 at 12:19
    Author: paul .a larner

    hi what is the "T" position an the pcb,are they grounds for the scope probes ie x-y?,ive build this but just seem to get a few diaganal traces superimposed on top of eachother,help,cheers m3vuv.

  5. Date: December 16, 2018 at 16:40
    Author: robert w

    Would most likely be better on a cheap cathode ray analog scope, nice simple implementation that most could build in an afternoon to make something useful.

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