2600 Hertz Single Tone Generator Schematic ------------------------------------------- Parts: 555 timer I.C. 8 ohm speaker | 9 volt battery & connector --+- = connection Pushbutton switch | 5k potentiometer 1k ohm resistor | 4.7 micro-farad capacitor ----- = no connection 3.3 micro-farad capacitor | +---+------------------------------ | | | | V 1k | | /\/\/-+/\/\/-+-------------- | +------- 5k | | | | | ---|--------|-------|--------|--- | | pshbtn | o | 8 7 6 5 | | | switch - | | | | | o ||| 5 5 5 | | | | ||| TIMER | | | | | | | | ()----- | 1 2 3 4 | | | 9 volts ---|--------|-------|--------|--- | | (-)-------------- | | | | | | +---------------------- | | 3.3uF | | | +-->|--------------------+--------- | | 4.7uF \_/ | --- | |() | | ______ | +---| 8ohm |---- /__SPKR__\ To calibrate: Play next to a pure 2600hz source and adjust the 5k potentiometer until the two sounds are the same. As you get closer you will hear a beat tone form and get slower and slower. When it stops, the two frequencies are equal. This takes a little practice.
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