LC Meter : DIY LC Meter to Identify Components

Here is LC Meter that you can build yourself, you can find the schematic, board design also included and description for building from Phil Rice VK3BHR



Another site sells this LC Meter and looks neat. It would help to identify the components easily especially for the radio amateur. Try to get it one.

" This is one of the most accurate and simplest LC inductance/capacitance Meters that one can find, yet one that you can easily build yourself. This LC Meter allows to measure incredibly small inductances starting from 10nH to 1000nH, 1uH to 1000uH, 1mH to 100mH and capacitance from 0.1pF up to 900nF. LC Meter's circuit uses an auto ranging system so that way you do not need to spend time selecting ranges manually. Another neat function is the reset switch that will reset the initial inductance/capacitance, making sure that the final readings of the LC Meter are as accurate as possible."
Link : http://electronics-diy.com/lc_meter.php

DIY Transistor Tester from eBay

Finally, my wish to have Transistor Tester from eBay is reached. I just bought the transistor tester on August 21. I don't want to make it myself because it seems like not worth my money and time. The price offered from eBay when compared with the price of buy components and time that needed to design it myself seriously unprofitable.

Imagine if I ordered from other towns ATMega328 IC, because nobody sells this in my city. I have to pay for about six bucks for one IC, plus transportation fee about two bucks. It has been already eight dollars. I have to take time to design itself with PCB software. 

Last, I need to buy other components like a resistor, LCD, capacitor, etc. This is really not worth time and money. You can purchase one from eBay for just about $15 bucks as a kit. Actually, I buy it with the money that I earned from writing articles. It is still useful as test equipment for my hobby.

The transistor tester that I buy come as a kit. The IC is ATMega328 DIP version, looks good for me because I can change it easier. The price I bought it for not too expensive at that moment, US$ 14.99. The drawback is we must install its components yourself. I decide to buy a kit version because already made version a little bit expensive and the advantage is I can still have the joy to assemble it. What makes me annoyed is the seller lower the price just two days after my purchase, the price goes down to US$ 14.21.

You can see below picture as seller example to show how it looks the assembled one.

Pretty good PCB, the space made for battery looks good too, and I can make the case from acrylic for this transistor tester. There are many variations on eBay, some use SMD IC, that’s the one make me consider to choose the DIP IC version. 

One more advantage about this, it could be powered by DC wall wart adapter. It seems like the seller doesn’t have a manual or know how to set it up. So I hope the components sent and the components name printed on the board is quite clear, so there is no difficulty to assemble it. 

Until now, the item still doesn’t arrive, hopefully, it could come faster. Maybe I'll create the manual for you who want to try purchasing from kits, just email me if you want it or maybe I’ll make a thread about this transistor tester manual from eBay later. Thank you for coming here.

ESR Meter Extension to Test Component Under Load

I made this add on for ESR Meter since I found something strange from my experiment. There is another way to test flyback or transformer which are still energized with bulb, but this add on still serve me well, so far so good. 



By the way, you could test yoke too with this add on for your ESR Meter and don't forget about the note. Have a good day and still be careful when doing repair job. Thank you for coming here.

See this great idea that I created and kindly post by Mr Jestine Yong on his blog. You can test flyback and SMPS transformer under load with this.

Link : ESR Meter to detect magnetic field

DIY Blue Ring Tester

If you are a technician, don’t miss this Ring Tester on your repair bench. It is rare to find Linear Power Supply on our equipment today because everything was made with SMPS today. SMPS or Switch Mode Power Supply offers an efficiency and more light than Linear Power Supply with the same performance. It is hard to find a big bulky transformer today on our consumer electronic equipments today because everything were dominated by Switch Mode Power Supply. 

The disadvantage about power supply which are difficult to troubleshoot because it’s complexity. We need a reliable tool to help us troubleshoot SMPS. You can’t depend on just one test equipment to repair SMPS, that is a hard job. I’ve found this tester really helped me to do a troubleshooting job. I would never do a repair job without this one because it helped me much.

I build this tester based on Blue Ring Tester schematic from Anatek Corporation manual. See below picture.

You can see I have tested one flyback which is shorted. The faulty fyback wouldn’t make Ring Tester led lit. It is just one or two led were lit if your flyback faulty, when you have a heavy shorted on your flyback, the led on Ring Tester wouldn’t lit at all. This is my Ring Tester when test a bad flyback.

This below picture when I test good flyback

You can see all led on the Ring Tester is lit. This is a sign for good flyback. Hold on, you must be surprised if you know what else this tester could do. What it is? SMPS Transformer of course! 

Did you ever find the faulty SMPS Transformer before? I have found several SMPS Transformer were shorted and I am wondering what if I don’t have this good equipment. Just build or buy it if you have a budget. 


You can find information on the internet. It is really worth your time and your money on this equipment. You can test SMPS transformer primaries with this Ring Tester. You would see the difference from good and bad SMPS transformer, you just need a little time to find your transformer was failed.

As professional technician, you have to do troubleshooting job faster. If you could repair one equipment in the shortest time a day, it means you can repair more equipment on a day ! 

I am not salesman from Anatek Corporation or elsewhere. I just found this tester really do his job well. I remember one day where I don’t have this tester yet. It was really hard to find the causes from dead TV. I am wondering is SMPS section or high voltage section (horizontal section) were defective. I have tested primary and secondary section, but I couldn’t find the culprit. I waste my time almost two hours to find the culprit and that is non profitable for a technician.

Don't forget to see my DIY ESR Meter design too

DIY ESR Meter based on Allan Willcox design

This time I want to share my story to make the distinct design of ESR Meter.

ESR Meter using 3 pieces of IC TL082 designed by Allan Wilcox and some components of his supporters. After I made the ESR Meter it is suitable to use in conjunction with the analog meter on my scale 100uA. The appointment of the needle not linear, so that to read the scale of 0.1 up very easily. The label on the box is the label that I took from a website that is on the label Blue ESR Meter made by Bob Parker. 

You can see below picture.

Please note, the ESR Meter can be equipped with buzzer sounds to indicate whether the capacitor we test good or not where we can set on how many ohm range buzzer will go off so we don't need to see the panel meters to shorten the time in the repair.

I print the layout with the wrong position so that IC should be installed upside-down, but with a little gently I have successfully completed and are very satisfied with the performance of this ESR Meter. I always fix the TV with the help of ESR Meter. Wanna see my first DIY ESR Meter? Look at this.

DIY ESR Meter

ESR Meter is not a new thing. Some are commercial and many DIY projects too on the Internet. I have ever heard my friend said "If electronics equipment still has bad caps, there are still many technicians.

I think ESR Meter really useful when you are troubleshooting some faulty electronic equipment, you can't tell just from capacitor looks good, because capacitor couldn't judge just by capacitance value, they have gone high in their "inner" resistor and make your electronics equipment failed.

As Wikipedia said ESR Meter is 

"An ESR meter is a two-terminal electronic measuring instrument designed and used primarily to measure the equivalent series resistance (ESR) of real capacitors; usually without the need to disconnect the capacitor from the circuit it is connected to. Most ESR meters work by applying voltage pulses to the capacitor under test which are too short to appreciably charge it; any voltage appearing across the capacitor is due to ohmic drop across the ESR. Measuring ESR can also be done by applying an alternating voltage at a frequency at which the capacitor's reactance is negligible, in a voltage divider configuration.

Other types of meter, including normal capacitance meters, cannot be used to measure a capacitor's ESR, although a few combined meters are available which measure both ESR and out-of-circuit capacitance. A standard (DC) milliohmmeter cannot be used to measure ESR, because a steady direct current cannot be passed through the capacitor."

ESR or Equivalent Series Resistance of real capacitors. Resistance??
Yup !! capacitor has a resistance, identically ESR like as a resistor that attached or added to capacitor capacitance. Below picture is the analogy example.



I take from a Wikipedia quote :

"Other types of meter, including normal capacitance meters, cannot be used to measure a capacitor's ESR, although a few combined meters are available which measure both ESR and out-of-circuit capacitance. A standard (DC) milliohmmeter cannot be used to measure ESR, because a steady direct current cannot be passed through the capacitor."

So it means we as repairer needs this tool after AVO meter or digital meter. I want to share my experience in building this tool. Actually, I get the schematic from another website.
So, I prepare the components to make this ESR Meter from here

Finally, my ESR Meter was done and I can't wait to test it. I found my wall wart adapter power supply has failed because one of capacitor gone high in ESR value, regardless no sign of bulging.  I replace the new capacitor and my wall wart adapter brought back to live. I have very happy had these tools on my repair bench because it's very useful. I conclude this ESR Meter really needed by a technician to search for a bad capacitor.