LAUNCH SEQUENCE
If you are using a smaller engine, you may want to do a final weigh-in before going ahead with a launch. With everything installed, verify that the total weight is within the capability of the rocket motor. If so, follow the rocket kit’s launch instructions. Here’s the basic sequence:
1. Check to make sure that the nose fits securely, but not too tightly. Then tie up the parachute, engine, and wadding. 2. Set up the launch pad per instructions. Make sure the field you are launching in is large enough; otherwise you’ll lose your precious payload. For a rocket powered by a D-sized engine, the field should be at least 500 feet in diameter. 3. Ensure that the rocket launcher is not armed (usually this means the key is removed) and then set up the rocket on the pad. 4. Turn on the camera and press the record button. The red record light, just under the lens, should come on. 5. Close the hatch and tape it closed. Although not typically rated for space-faring use, ordinary masking tape works fine. 6. Start the countdown and launch. 7. Recover the rocket. Open the hatch and press the Record button to stop recording. The recording light should turn off. Then turn the camera off by pressing the On/Off switch. If you forget to turn the camera off, it will switch off automatically after a few minutes of non-use. Do not turn the camera off by removing the battery. 8. Back at your computer, hook up the USB cable, download the video, and enjoy.
WATCH IT
Watch a high-flying video captured by John Maushammer’s Rocket-Launched Camcorder at makezine.com/07/camerarocket.
UPGRADES
Downward View During Descent If you installed the downward-facing mirror, you’ll get a whole new view of the launch. One drawback, though, is that the descent will typically have views of the parachute and sky. You can change this by attaching the parachute to the tip of the nosecone instead of the base. Add a small eyehook to the nosecone’s tip, and run the parachute cord along the side of the nose and into the body.
Improved Resolution
The CVS camera (which is manufactured by Pure Digital, along with the Rite Aid and Target cameras) actually has a 640x480 sensor. But in order to extend recording time, it is configured to record at only one quarter of this resolution. Recording time isn’t a problem for rocket flights that last only a few seconds, so you can set the camera to record at the full resolution. You can do this by uploading a modified version of the binary file USP. BIN into the P3 directory of the camera. See Resources, below.
RESOURCES Estes Engine Chart makezine.com/go/estes Determining Center of Pressure makezine.com/go/cop Downloader software makezine.com/go/software Improving image resolution makezine.com/go/resolution
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