How does the TDS sensor circuit convert DC to AC and what is the CD4060 output voltage?

this part of circuit is used  in TDS (total dissolved solids) sensor module for arduino. The thing is that this part converts DC to sinodial(positive and negative) voltage levels , how it is doing this ,i ,i am unable to understand.  
2) please also tell me that will be output voltage of this cd4060 ic. 

OK, the components around Pins 9 & 10 will generate a clock with a period of around 220 us according to the datasheet for the 4060 here.   That's a frequency of around  4500 Hz.  The Q4 output is the clock divided by 16, so around 300 Hz.  This will be a square wave from 0v to around 3V (VDD of the 4060).The LM324 operational amplifier will amplify this by a factor of minus  6.8/100 (the ratio of the resistances) so your output will be a square wave from roughly 0 to minus 200 mV.  It will NOT be sinusoidal as there is no filtering of the signal.If I have time I'll try and put this circuit into a simulator and see if I am correct here, (or you could do that!)