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Bicycle Crystal Radio 2022

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Candy Can Crystal Radio

   Candy Can Crystal Radio A crystal radio allows you to listen to radio without battery. All the power comes from harvesting energy broadcasted by the radio stations. Modern crystal radio components allow us to listen to AM, SW and FM radios without battery. I just built a crystal radio on a Japanese candy can. I bought the can when I toured in Japan around 2019 before the COVID. I had thought of putting a crystal radio into it since then but forgot about it until I found it underneath my bed last week. When I was figuring the layout of knobs and jacks on the can, I kept the cap so I can still put candies into the can . This way I can listen to the radio while enjoying the candies. This is a standard MOS FET 3DQ circuit with only 6 components : 3DQ, 220uH ferrite toroid coil , 20pf to 380 pf plastic VC, 4700pf capacitor for low pass filter, 500 to 2K earphone, telescopic or long antenna and ground. Here is the video of the design, build and testing. Here is the video to show you h

Float Valve for passive (Kratky) hydroponics with base

Float Valve for passive (Kratky) hydroponics  with base Kratky hydroponics is a passive non-circulating non-wasting and environmental friendly method for growing plants with Nutrient Solutions instead of soil. The original Kratky method uses a big tank with the right surface area and depth that will hold sufficient Nutrient solutions for the plants to grow from seedlings to harvest. You can find more about this in my other blog post here. While this method works well for non-thirsty plants such as lettuce and other vegetables, you need to modify it to work for other more thirsty plants such as tomato and most fruits. The modification involve storing a lot of Nutrient solutions in a big tank around 30-50 litres big lifted up one feet to 3 feet higher than that of the growth tank. This will  create the gravity pool for the Nutrient to flow down the rubber pipe to get to the growth tank. Then install a float

3D printed AM SW FM Portable Crystal Radio

  Introduction Im my previous video, I showed you how to create a tiny portble crystal radio.  I understand that it's hard to find such small components and chasis. So I created a 3D printed chassis to fit bigger components. A bigger transformer to drive the speaker without battery. Here is the video of the 3D design, build and testing. Here is a video of a similar radio but in a much smaller chassis. Here is the video to show you how to make the coils, and other components used in this radio. You can view my previous video for details about the circuit. The Circuit Follow this circuit if you are using 3DQ's. Follow this circuit if you are using Diodes. The Chassis  The 3D printable models can be found here. Full size chassis Half-size  small chassis. Where to buy components L inks to components you can get from e-Bay to make this radio. eBay MOSFET 3SK143-Q 3DQ for Crystal Radio "Zero-Volt