I am working on solar pendulum by solarbotics. here is the circuit:
I used everything as stated except the coil, magnet and power source.
I extracted a magnet from a tiny speaker (dia = 1inch) and I made the coil using 26 gauge wire (100 grams of it). I am using my mobile battery (4V) as a power source. The coil is big and strong enough for the job.
As said in the pdf, the circuit should turn on momentarily when the magnet passes over it and provide a little nudge to keep the pendulum swinging.
But I was not getting the same result. My coil was permanently energized. I get continuous drop of 1.6V across the coil. my 3904 transistor remain cool but 3906 gets heated while operation.
Some one was saying that it has to do with natural frequency of the circuit namely root under L*C and the frequency of pendulum should match with the frequency of the circuit.
I used everything as stated except the coil, magnet and power source.
I extracted a magnet from a tiny speaker (dia = 1inch) and I made the coil using 26 gauge wire (100 grams of it). I am using my mobile battery (4V) as a power source. The coil is big and strong enough for the job.
As said in the pdf, the circuit should turn on momentarily when the magnet passes over it and provide a little nudge to keep the pendulum swinging.
But I was not getting the same result. My coil was permanently energized. I get continuous drop of 1.6V across the coil. my 3904 transistor remain cool but 3906 gets heated while operation.
Some one was saying that it has to do with natural frequency of the circuit namely root under L*C and the frequency of pendulum should match with the frequency of the circuit.