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.