Magnetic Apogee Detector
Using the earth's magnetic field, the Magnetic Apogee Detector can sense when a rocket has reached its maximum altitude so that an e-match can be fired to ignite the black powder which in turn pressurises the body tube causing the parachute to deploy.
Upon opening the packaging I was very surprised to find chips, resistors and capacitors smaller than the head of my soldering iron ! So challenge number one was to solder with a hefty soldering iron great, secondly I was slightly concerned about the fact that if one of them fell on the floor I would never find it again.
I decided to set aside an area for soldering only opening the components when they were needed. However before I started I read through the instructions at least 5 times to try to get a clear picture of what was going to done.
Starting with the resistors, capacitors and small ICs (and I mean small) solder them to the circuit. Pay attention at this point, because inadvertently I placed a chip the wrong way round and had to re-solder it later. After that it is simply a case of adding a switch on to the terminal block and the battery, well so I thought...
The instructions say add a resistor between either points C and E or E and D there are 5 possible values for this resistor and this is where a good multimeter, a lot of patience and guess work come into play. I tried various combinations, and nothing seemed to work, until someone told me to put the 1.5 M Ohm resistor between E and C. Tried it but it still didn't work, using guess work I assumed that if the person was correct then the value I needed would be close to that , so I decided to opt for the 2 M Ohm resistor due to the fact that if you know a rough value then go for a resistor slightly higher than that.
SUCCESS !!! the MAD now gives 9.5 volts when tilted 20 degrees from vertical.
Pictures:
Above are pictures or the kit components and the earth's composition in relation to field lines. Below are pictures of my MAD. (Click on them to view larger pictures)
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