High torque encoded DC motors for robots from car window motors

Hi! As I mentioned in my latest post on how to make Tiny Encoders for DC Motors, some time ago I went to a junkyard to salvage two powerful high torque DC motors from car window lifting systems to use in a robot. I had to take my own tools and dismantle the doors from an old Renault Laguna myself  to get the motors and then managed to negotiate with the seller to buy both motors for 25€, which I think was quite cheap.

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Experimenting with vacuum molding

Hi there! This post is about a really simple way of making plastic parts for your projects. Have you ever heard of vacuum molding? It's a method to make a plastic mold of a piece by using heat and suction from a vacuum cleaner. You can easily replicate what I'm going to show you. You just need some wooden pieces to make a box like the one you'll see in the picture, a vacuum cleaner, a heat gun/electric heater/oven and some disposable plastic dishes.

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Adding an external power supply to a cheap USB hub

Hi again! In this post I'm going to show you how to add an external power supply to a cheap USB hub. :)

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I've been running some experiments with two Logitech Quickcam for Notebooks Pro and the Raspberry Pi and unfortunately I haven't been getting any good results. I can't get many fps and some of the captured frames contain corrupted data but I think I may have found out the reason for that. After some reading I verified that the USB ports of the Raspberry Pi can only source 100mA to a device and maybe the cameras are consuming more than that. To bypass that problem I went out to buy a USB hub with external power supply.

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Inexpensive CD Wallet Electronics Tool Kit

Hi! Maybe you're an electronics student, maybe you're an electronics hobbyist, maybe you just had the misfortune of being reading this blog and finding this post :P Anyway, you might find it useful. I'm going to describe how to make an inexpensive (20€), small and portable tool kit with the essential tools for some electronics experimenting or some practical lectures at the university's labs.

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Fixing Digital Calipers

Hi there! In this post I'm going to show you how to fix a digital caliper in a very easy way. In fact, it's so easy that I had serious doubts about it until I tried and saw the results with my own eyes. :P

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Low Cost (1,85€) USB to RS232 LVTTL Serial Cable

Hi there! Have you ever needed a USB to RS232 converter to connect to your microcontroller for serial communications? If you have, you probably bought a USB to RS232 converter and then used an external MAX232/DS232 to convert the RS232 voltage levels to TTL levels. That requires a little money, and a little work too. However, there is a simple cable that converts USB to RS232 with LVTTL levels (fully compatible with TTL). Basically you just need to change the connector. The last one I made cost me only 1,85€ with shipping included! :D If you only buy an FTDI chip it will cost you almost the double! (yes, I know that FTDI chips are probably the best USB to RS232 converters but most users don't take require the full features and specifications of an FTDI chip).

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