How to Operate the Transistor Tester With AVR Microcontroller

This Instructable is meant to be a companion to the Instructable where I showed how to assemble this device.

I'll show what it looks like when you power it up, how and why to calibrate it, and how to measure various things.

*** Note: During the course of my exploration, I actually fried my tester..... I already had another one on the way, so I'll build another one. However, hopefully you do not fry yours. I'll describe what I was doing at the end of this Instructable. If you use a 9v for testing this whole time, don't worry about it. If you are "experimenting" with different power sources....or how to measure voltage with this thing....perhaps see the end of the Instructable first.

Step 1: The Testing Ports

The tester has several points where tests can be run, for this short demo, i'll show the ZIF socket. See the picture for where the test points are.

You can put the ends of your part in any two ports to get a reading (for those with two wires). I generally use one and three in the examples.

Step 2: Turning It On, Setting It Up

First, connect a 9v battery, or a 6 to 12 volt DC supply to the barrel power jack. In this example I'm using a 9v battery. Press the silver knob down to "start" it up. As nothing is plugged in to test, it may show you the *warning* that it is not calibrated.

Step 3: The Menu

Scrolling through the menu gives you these options. This Instructable will hardly scratch the surface of the capabilities of this thing -- (at least initially -- I'll update as I continue to use it and understand it). For those more technically inclined than me, this manual explains everything.

Step 4: Calibration - Prep

To calibrate, as it describes, you must connect all three testing spaces with whatever "probes" you plan to use. For this example, I plan to plug the parts directly into the testing places, so I put together a little thingy which I just place into the ZIF for calibration.

Step 5: Calibration - Into the Test

If you are going to use probes or leads to do your testing, then have these connected to each other to allow calibration when you startup the tester.

Step 6: Measuring Resistors - the Resistor

Step 7: Measuring Resistors - the Tester

You can select the Resistor symbol from the menu, or just start the tester with a resistor already connected up. The following blurb is an excerpt from the manual:

"Resistor meter With the 1 3 symbol the tester changes to a resistor meter at TP1 and TP3 . This operation mode will be marked with a [R] at the right side of the first display line. Because the ESR measurement is not used in this operation mode, the resolution of the measurement result for resistors below 10Ω is only 0.1Ω. If the resistor measurement function is configured with the additional inductance measurement, a 1 3 symbol is shown at this menu. Then the resistor meter function includes the measurement of inductance for resistors below 2100Ω. At the right side of the first display line a [RL] is shown. For resistors below 10Ω the ESR measurement is used, if no inductance is find out. For this reason the resolution for resistors below 10Ω is increased to 0.01Ω. With this operation mode the measurement is repeated without any key press. With a key press the tester finish this operation mode and returns to the menu. The same resistor meter function is started automatically, if a single resistor is connected between TP1 and TP3 and the start key was pressed in the normal tester function. In this case the tester returns from the special mode opration to the normal tester function with a key press."

Step 8: Measuring Resistors - the Results - 1000k Ohms

Step 9: Measuring Resistors - the Results - 100k Ohms

Step 10: Measuring Resistors - the Results - 100 Ohms

Step 11: Measuring Capacitors - Startup

"Capacitor meter With the 1 3 symbol the tester changes to a capacitor meter function at TP1 and TP3. This operation mode will be marked with a [C] at the right side of the first display line. With this operation mode capacitors from 1pF up to 100mF can be measured. In this operation mode the measurement is repeated without key press. With a key press the tester finish this operation mode and returns to the menu. In the same way as with resistors, the tester changes automatically to the capacitor meter function, if a capacitor between TP1 and TP3 is measured with the normal tester function. After a automatically start of the capacitor meter function the tester returns with a key press to the normal tester function."

This table is shows what we should expect for some of these capacitors:

*Found at this website

Step 12: Measuring Capacitors - 10 Nanofarad Ceramic Capacitor

Using this nanofarad to microfarad converter, and the previous table, we should find this capacitor labeled "103" to be measuring at around 0.01 μF == 10 nF.

Step 13: Measuring Capacitors - 100 Nanofarad Ceramic Capacitor

This 100nF (.1μF) capacitor labeled "104" measures in at 95.18nF (.09518μF)

Step 14: Measuring Capacitors - a 10μF Barrel Capacitor

Step 15: Measuring Transistors: a Bipolar Junction Transistor (BJT) - NPN

I won't pretend to know anything about these, except to put the right ones in the right place as directed by smarter people. However, this example shows the result of measuring one, and I've provided some details from the spec sheets to see how it measures up.

References used:

The 2N3904 NPN Transistor summary, and the datasheet for it, and another datasheet for it.

Step 16: Measuring Transistors: BJT-NPN Result

from the manual, regarding transistors:

"For normal measurement the three pins of the transistor will be connectet in any order to the measurement inputs of the TransistorTester. After pushing the start button, the Tester shows in row 1 the type (NPN or PNP), a possible integrated protecting diode of the Collector - Emitter path and the sequence of pins. The diode symbol is shown with correct polarity. Row 2 shows the current amplification factor B or hF E and the current, by which the amplification factor is measured. If the common emitter circuit is used for the hFE determinatation, the collector current Ic is output. If the common collector circuit is used for measuring of the amplification factor, the emitter current Ie is shown. Further parameters are shown for displays with two lines in sequence, one after the the other in line 2. For displays with more lines further parameters are shown directly until the last line is allready used. When the last line is allready used before, the next parameter is shown also in the last line after a time delay automatically or earlier after a key press. If more parameters are present than allready shown, a + character is shown at the end of the last line. The next shown parameter is anyway the Base - Emitter threshold voltage. If any collector cutoff current is measurable, the collector current without base current ICE0 and the collector current with base connected to the emitter ICES is also shown. If a protecting diode is mounted, the flux voltage Uf is also shown as last parameter."

Step 17: Measuring Transistors: a Bipolar Junction Transistor (BJT) - PNP

The 2N3906 General Purpose Transistor datasheet, and another one here.

Step 18: Measuring Transistors: BJT-PNP Results

Step 19: How I May Have Fried My Tester

***update after publishing! The picture above is something I did not pay attention to, it is from the original Instructable for the HackerBox kit!***

So, I was trying to see how this device might test for voltage, and I put a 5v 1A charge on those blue screw connectors on the board. None of them showed any signs of measuring voltage, some made the screen blink, and then after that....no more testing....the device doesnt work anymore.

Once I get my next kit in, review it, and assemble it, perhaps I can provide more useful info. Have fun!~