Activities/Turtle Art/Using Turtle Art Sensors: Difference between revisions
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The tuned circuit capacitor, two sheets of aluminium foil approximately 10cm x 10cm sitting loosely and separated by cling wrap gave a resonant frequency of approximately 1MHz with the above inductor. | The tuned circuit capacitor, two sheets of aluminium foil approximately 10cm x 10cm sitting loosely and separated by cling wrap gave a resonant frequency of approximately 1MHz with the above inductor. | ||
The 0.1uF capacitor can be made in the same way, the tuning capacitor is estimated at 100pF (10^-10 F) when sitting loose. The coupling capacitor needed is of the order of 0.1uF (10^-7 F). Tightly rolling the layers reduces the plate separation and a workable coupling capacitor was made by tightly rolling only 10cm x 10cm plates. | The 0.1uF capacitor can be made in the same way, the tuning capacitor is estimated at 100pF (10^-10 F) when sitting loose. The coupling capacitor needed is of the order of 0.1uF (10^-7 F). Tightly rolling the layers reduces the plate separation and a workable coupling capacitor was made by tightly rolling only 10cm x 10cm plates. | ||
The diode is still required. The original cat's whisker was made with galena crystals. | |||
The diode is still required. The original cat's whisker diode was made with galena crystals. | |||
==Links== | ==Links== | ||