E-tracer Tube tester, Curve Tracer and more


This is a new made digital tube tester by Chris Chang from Taiwan, who is doing such an excellent job here. This tester, same as a few others is a so called pulse tester, meaning it tests the tube with very short pulses, which keeps the power supply at much lower cost compared to full power testers like the Sofia, Roetest, and AT1000. This will reflect of course in the price, the dimensions, and the complexity of the internals, which is all positive. The tester is purchased as a working Printed Circuit Board, and hardware along with it, but for the rest it is a kit. Optically it reminds me of the Sofia, also internally, but the Sofia larger size, inside and outside.

What is good about the E-tracer?

Oh....many things! This list will be long. It is unfinished. I will have to add a lot more.

  • First, a pulse tester has no high power electronics inside. Anything which gets hot and has high voltage at the same time, suffers under reliability issues. Degradation is simply higher. So when the E-tracer get older, you won't have such problems. The day will come when you value this.
  • A perfect web page, you find it here.
  • Support. I do not get paid by Chris, and no free samples too. This information here is neutral. Support is in one word: Excellent. Unlike what I get from Amplitrex (close to nothing, though we bought three testers).
  • Weight and size. I sold my Neuberger 375 analog tester, because of it's crazy weight. The Neuberger 375 hurt my back a few times, so I did away with it. Other testers like the Hickok 750 fill a complete working place. Since you need also a PC with this tester, size is an issue, and the small size of the E-tracer is really good.
  • With the pulse testing method, you are only one step away from drawing tube charts, so the E-tracer of course has this option. Once you have the charts, you can pencil in the load line, and construct your own amplifier that way, but hold on.... Chris is working on a software for that. Read the rest:
  • The software. I never had the chance to test an E-tracer, but from my many Emails with Chris, I can say he has put great effort in getting as much as possible features inside. I just mentioned I made always so much use of the possibility to save the tube curves with the Sofia, and then load them later on, to analyse the dynamic parameters of the tube in any working point. That was done by a marker. After a while it was simple DONE. So soon E-tracer will be able to do load lines for a tube, and my next question is for distortion results, and power output, because we all want to know that, while designing a tube amplifier. I have some computer aided software myself, which can do that, but this is NOT really easy software, and the difficulty with that software is also, the number of tube charts is limited to what the software has inside. And no way to add charts. So if Chris can get that working for any new tested tube, that would sure be a good reason to buy this tester when you design amplifiers.
  • The voltage and current specifications is a stunning 750 Volt, 300mA. So that would means 232 Watt, but it is only a pulse of a few seconds. In the end, neither the electronics, nor the tube will heat up from this.
  • So you have to see what you get here is a tester that can do very high voltage, very high current, and offers a great set of software features, which to operate with the tube charts, instead of just printing them for you.
  • Pulse mode is not a totally ideal way to test, but for that you will hardly burn down a tube by mistake.
  • This Article is in preparation, and not complete!

What is not good about the E-tracer?

  • Actually there is very little wrong with it. Just I want to say here what i know.
  • Cold anode testing can give false results with used tubes. In case of doubt, over heat the tubes with 5%. If this gives a change in plate current, this is what I talk about. Such tubes would give even better curves if the plate current was normal (so not just impulse testing) and normal plate heat would add to it.
  • It is able to damage the tube heater by false settings. Like put 27Volts on a 12Volts tube. Only a fool will do so, but the e-tracer just accepts it. I think the heater over voltage should be limited by maximum 20%. I have written a note about this to Chris Chang, waiting for his reply.
  • You do need to read this part about pulse testers in general


  • Please look here for a complete compare of this tester with the others.
  • My opinion on this tester is based on the many discussions I had about it with Chris Chang, and based on the compare page I have with other digital testers, for which Chris provided me the information, and he worked very hard on getting maximum numbers on green fields there. So he wants to get the best out of it. I said it before, this product is designed with pride and very well done.
  • This is the best product of it's kind. Not cheap, but highly recommended