My journey of making my first-ever circuit. | by Khwawja Maaz | Jun, 2026 | MediumSitemapOpen in appSign up<br>Sign in

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My journey of making my first-ever circuit.

Khwawja Maaz

5 min read·<br>9 hours ago

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The reason I started this project in the first place was that I needed a way to implement head tracking for my game (DCS). The normal headtracking, which is basic and uses the geometry of faces to track, requires light, and by nature, I like to play games at night, as at that time there is more peace and just a vibe to play. However, at night I have to turn off my light as my brother and I share the same room, and for him to sleep properly, the lights must be turned off. Hence, I can’t utilize headtracking, and without it the game is not immersive, and my performance declinesas Ii have to use the mouse to move my head around in-game. Hence, I decided to build my first circuit in my life by myself to build a TrackIr DIy device.<br>Since it was my first circuit without any assistance, I had to buy the equipment. Soldering was one of my biggest drawbacks, as I have never used it properly in my 16 years of life. The concept of wiring wasn’t an issue as I had studied O-Level physics and I made a small circuit diagram to help myself.

I asked Gemini and watched some yt toturails to help me out with this track IR stuff, and after watching like 20 videos, I was feeling confident. For my next step, I went online to buy the resistors, soldering iron, LEDs, and multimeter, and I bought everything extra just in case. If I mess things up, I can redo the circuit all over again.

When I got the package, I unboxed it with excitement and got ready to work on it on Saturday(20JUN). It took me 20 mins just for the diagram of the track IR to be drawn on the cardboard, and then an additional 25 mins for cutting it.

Here is the blueprint I usedIt took me a full day to complete 60% of this, but I was getting used to it. The main drawbacks were that my soldering iron was oxidized, and I didn’t know how to deoxidize it (electrolysis at home wasn’t an option), and I didn’t know about the tip cleaner and brass sponge. It took me a lot of time to solder the rest of the wires with LEDs, and I was skeptical that I burned the resistor or the LEDs while soldering. After all, the circuit was complete. I thought the thing was finally done, but I was wrong, and I started to get my first errors.<br>ERROR 1:<br>My cardboard structure was not strong enough, and it was falling off. It was because the width of the cardboard leg was not large enough to support the weight of the lead at the end.

The joint is weakERROR 2:<br>One of my biggest mistakes was that the Gemini told me in error that a large leg of LED is negative and a small one is positive, and Ididn't fact-checkk .t, Hence, my whole circuit was reversed bias, and none of the lights worked. You see, 940nm wavelenght of the LED is way more than the human eye can see. The human eye can only see from 400–700nm, and to check that the LED is working, I have to use my phone camera, as it doesn’t have an IR filter which isn’t installed, to make sure the face pictures are crystal clear without missing much detail.<br>I tried using my phone, but I didn't see any light at all. I tried it with my air conditioner remote, which has an LED, and it was lighting up in the camera.<br>ERROR 3:<br>My calculations were wrong. In fact, I didn’t do any calculation at all; I completely relied on Gemini, as my Claude wasn’t workin,g anitIt told me that I needed a 47-ohm resistor, and I bought it along wiht 39&56 ohm resistor just in case. And that supplied too much current, which is unsafe for LEDs.<br>TROUBLESHOOTING:<br>And now I figured out that I need a 220 OHM resistor to ensure the current in the circuit doesn't exceed 20mA<br>Press enter or click to view image in full size

Using the formual I=V/RYou might be wondering why I didn’t use the full 5V from the us b, Its becuase not all voltage is going into the resistors. In series, the voltage divides; hence, 3.3V is used by the LEDs.Since the current is the same in series, I can say 0.07 A will be supplied to the LEDs. But the ideal range for the LED is between 8 and 15 mA. To ensure my LEDs are properly powered, I will ensure the current is atleast 9mA hence i iwll use a 180-ohm resistor.<br>Secondly, at the time, I had no idea my connections were reversed. It took some help from an online friend, but I eventually got it.<br>As of right now, I'm waiting for my 180,200Ohm resistors along with the<br>1- Soldering Iron Paste/Tip cleaner<br>2-Solderingg Flux<br>3- 1 Brass sponge<br>My next step will be to make another base with cardboard, ensuring it's strong enough with a double layer and properly soldered joints.<br>I find this hobby very interesting, maybe, who knows, maybe i persue carer in this field. Hey, you gotta start somewhere, right?.

Electrical Engineering

Engineering

DIY

Written by Khwawja Maaz<br>0 followers<br>·1...