I frequently use an IR LED extension cable for home appliance automation in my work. Testing the IR LED requires the use of a multimeter, which I find inconvenient when only testing the IR LED. This is especially true when I have a large number of IR LEDs to test. To alleviate this issue, I created an IR LED tester to reduce my workload.

For the sake of portability, I plan to put the IR LED tester into a 4-cell battery box. With a simple circuit that utilizes the diode unidirectional conduction principle and a current limiting resistor, I was able to achieve the goal of testing IR LED extension cables.

Supplies

Custom PCB x 1

200 Ohms resistance x 1

3.5mm headphone socket X 1

3mm LED X 1

AAAx4 battery box X 1

screw, nut, meson X 2 Set

Step 1: Supplies

As mentioned earlier, by utilizing the diode's unidirectional conduction principle and a current limiting resistor, if both the tested LED and indicator LED are correctly connected, all LEDs will light up. If the tested LED is reverse-connected or open circuit due to malfunction, the indicator LED will not light up.

Lastly, due to the presence of the current limiting resistor, if the tested LED is short-circuited or used to test the wiring, the indicator LED will light up brighter than usual.

Step 2: Make a Custom PCB

I hope to make it as small as possible, so I am using SMD components as much as possible.

I use EasyEDA to design PCB and upload the design to JLCPCB.com to manufacture PCB.

JLCPCB make high quality prototyping PCBs for people all over the world. They have over 300,000 worldwide customers with over 8000 orders per day! They have over 10 years of manufacturing experience and are super reliable. Try it for your self and get 10 PCBs for just $2 at JLCPCB, New registered users US$54 offer , Order here

You can use my gerber files to ordel your own PCBs, and build this DIY Project.

Just a quick example how to order PCB from JLCPCB.com:

1)press "QUOTE NOW"

2)press "Add your gerber files"

3)upload zip or rar

4)all properties could be left default

Step 3: Solder

In just a few days, I received the custom PCB from the factory and was able to enjoy the DIY assembly process. I used a regular soldering iron to demonstrate how to solder SMD components. With the help of the custom PCB, I was able to assemble the entire quickly and easily. The entire assembly process can be viewed on YouTube

Step 4: Modifi Battery Box

To improve the modification of the battery box, I welded a PCB with only a 3.5mm headphone socket to make it easier to drill the holes. The entire modification process only required a 3mm and 5mm drill bit. After installing the PCB in the battery box, it was secured with screws, and both screws served as testing points.

Step 5: Test

Step 6: Detail Tutorial

With the help of custom PCB manufacturing, I was able to easily create the Simple IR tester with just a few simple steps.I hope everyone enjoys my creation.