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Misc Hacks4186 Articles
Weather Satellite Station
This page describes one group’s experience setting up a receiving station for NOAA weather satellites. To receive the images you first need to track the satellite you want to receive from. After tuning your receiver to the satellite’s frequency you can record the audible data stream using your sound card. You can decode this data either real-time or later. They went through several system iterations using both free and commercial tools.
Connecting DECT Phones Through Sound Cards For Asterisk
I couldn’t think of a better title. Here’s how it goes: [onno] wanted to convert a DECT phone for VOIP use. First he tried using transformers for the audio, but was unhappy with the noise and echo. He describes how to do a direct tap like [Christoffer]’s Skype phone, but includes all of the necessary measures to keep from frying your sound card. The main piece of this project is his hacked “chan_oss” driver for Asterisk. Using the driver, Asterisk is able to ring the DECT phone. It also detects whether the phone is off-hook by comparing the sound input to the known line noise level. The phone can dial using DTMF just like any standard phone.
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Wearable LED Display
Following these instructions you can add an LED matrix to almost any piece of clothing. The whole display can be controlled using one output for each vertical and horizontal thread. The first step is to solder crimping beads onto each surface mount LED you will be using. Next sew a grid of conductive thread into your garment keeping the vertical and horizontal threads on opposite sides of the fabric. Each of these threads is terminated at a sewn on microcontroller socket. The LEDs are sewn on at each thread junction. She doesn’t have any code posted yet unfortunately, but there is an example movie of Conway’s Game of Life.
[thanks lobo]
Crutch Tripod
Doug Nelle uses this super cheap tripod to support his 5″ f/5 refractor telescope. The wooden structures are constructed out of oak. Doug has inserted dowels into the tops of the tubes to keep them from collapsing under load. If you want to build one for yourself [yo_tyler] suggests checking local thrift stores.
Rocket Altimeter Project
This project is a really simple accelerometer based altimeter. The assembled board only weighs 10grams; the power supply is an additional 6grams. The data collection is done by a Basic Stamp II. It records 1 second before and 11 seconds after it detects the initial launch thrust. On their first launch they got some legitimate looking data (it would have been nice if they had an inclinometer to compare it to). The second launch resulted in a catastrophic engine failure on the pad. It’s a shame they couldn’t do more testing, but at least they’ve got video. Schematics and source code natch.
The photo above is from a recent BoingBoing post on high power rocketry.
Microgram Electrobalance
As with most precision equipment, microgram scales are usually very expensive. The close tolerance machining of sapphire pivots and computer control add to the cost. Not all of those components are necessary though. This article from Scientific American demonstrates how to build a simple microgram balance using a salvaged galvanometer. Once calibrated, the output voltage will have a direct linear relationship to the weight. There is a more recent version of this project that uses a microcontroller to overcome static friction and auto center.
