High-Brightness LED Green Test-Tube Light / Automotive Electronics DIY

That’s the light (points)! I once saw a car enthusiast’s comment on an automotive fan forum: “It’s precisely because our cars fall short that we must find ways to strengthen and make up for it…” — which struck a real chord with me.

But our cars’ shortcomings are also reflected to a considerable degree in their price, so I don’t think of it as a shortcoming, but rather as our demands being too high (gazes into the distance).

Since the new car I bought has already passed its three-year factory warranty, recently, in between studying for graduate school, I’ve also gotten the urge to give the car a good overhaul. But my demands for the car’s comfort and appearance far exceed those for power, so as far as power goes, aside from replacing the “iridium spark plugs,” using good quality maintenance oil, occasionally adding fuel additive, and once in a while switching to pricey 98-octane unleaded to flush the fuel lines, I probably won’t make any further changes.

After all, if you really want a car that’s impressive and can really run, rather than wasting time and money on modifications, it’s more practical to just buy a supercar (smirks).

Today’s automotive electronics DIY was done to fix a small shortcoming I have with my glove box — “no light” — so I did some circuit design and implementation.

The first version shown below, the “black version,” was a test version and a failed piece of work. Trying out a newly bought gas soldering iron for the first time, I found it hard to control, which made the heating time drag on too long, and one of the high-brightness LEDs burned out — only three of the six could light up (the circuit design used three per group, two groups in total).

“Black version” LED green test-tube light test version

The image below is the second version, the “silver version.” I went back to my own dedicated traditional soldering iron, the temperature control was stable, and this time it was completed smoothly and quickly.

I also added a long-handled micro switch, bent the handle a bit for shape, and placed it in a suitable spot in the glove box. From then on, whenever the glove box is opened, the test-tube light glows and provides illumination.

“Silver version” LED green test-tube light, assembled version

That said, the first failed black version actually pained me quite a bit, because the “piranha LEDs” used this time were bought a few days earlier out of laziness at a shop on the streets of Tamsui.

Although I knew this electronics shop in Tamsui was much more expensive than those in Taipei, I never expected it to be this expensive — several times over (NT$25 per unit, versus an online price of NT$38 for 5 units at Liangxing).

If I hadn’t had the sudden urge to make this test-tube light, I probably would never in my life have wanted to buy anything from that electronics shop. And not only did the parts they sold not come with a datasheet for us to look at, the owner couldn’t even tell us the model number or applicable voltage. I really don’t know how that shop has managed to survive this long.

Back when I was studying in the electronics department of Hsinpu Junior College of Technology (now St. John’s University), we used to frequent this shop often.

What’s funny is that when I tried to haggle, the owner’s wife put on a troubled expression and said this price was already the lowest (yeah, right). Hearing her say that, I was truly speechless. I was in too good a mood to talk back at the time — anyway, I’d already planned to go home and write up this bad shopping experience in this short piece, “any resemblance is purely factual” (I’ll treat that price as the cost of advertising for that shop).