Radio switch schematic |
Follow the schematic diagram to wire in a power switch and a red LED power-on monitor light.
Guide |
Parts required, 1 LED, 1 resistor, 1 SPST or SPDT (for a future add on) toggle switch. Use the LED wiring guide pictorial and schematic to determine proper LED polarity.
Testing the LED power on/off indicator circuit. The resistor value of 820 ohms was determined with the use of a resistor ohm substitution box. |
The 3mm red LED costs NT$1 each (US$.033 each) in a package of 100. The SPDT toggle switch SW1 is priced at NT$18 (US$.60). The resistor R1 is 820 ohm or the next larger resistance.
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FM Radio Station Part 5 Index
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