Since an oscillator is the simplest clock generation source creating a single output frequency from a single component (1) at the core of all circadian clocks is at least one internal autonomous circadian oscillator . These oscillators contain positive and negative elements that form autoregulatory, feedback loops, and in many cases these loops are used to generate 24-hour timing circuits. Components of these loops can directly or indirectly receive environmental input to allow entraiment of the clock to environmental time and transfer temporal information through output pathways to regulate rhythmic clock-controlled gene (CCG) expression and rhythmic biological activity (2).

Screen Shot 2014-07-14 at 11.56.46 AM

Some key principles of circadian biology

We’ll use this logic to study the temporal coordination of internal biological processes which are evidently crucial for survival of diverse organisms from bacteria to humans. An in order to understandand the phenomena of frequencies we started converting a 9v signal  in to a sound via an TC 4584 operational amplifier. We used 3 of 6 oscillator found on this integrated circuit to turn this signal in to a periodic sound wave making a voltage control oscillator with 3 voltage controls and 3 frequency controllers.

Screen Shot 2014-07-14 at 11.45.26 AM

Hex Schmitt trigger

The TC4584 is a Schmitt trigger a comparator circuit with hysteresis, implemented by applying positive feedback to the noninverting input of a comparator or differential amplifier. It is an active circuit which converts an analog input signal to a digital output signal. The circuit is named a “trigger” because the output retains its value until the input changes sufficiently to trigger a change. In the non-inverting configuration, when the input is higher than a certain chosen threshold, the output is high. When the input is below a different (lower) chosen threshold, the output is low, and when the input is between the two levels, the output retains its value. This dual threshold action is called hysteresis and implies that the Schmitt trigger possesses memory and can act as a bistable circuit (latch or flip-flop). There is a close relation between the two kinds of circuits: a Schmitt trigger can be converted into a latch and a latch can be converted into a Schmitt trigger.

Download (PDF, 1.14MB)

 

image 3

We are looking to use the internal oscillators from algae, bacteria or other  biosource to control our analog sound oscillator. So the latch pin in the IC is regulated by the clocking coming from the signals of different living matter.

In the first stage we start with the design of the tree oscillator module on protoboard. At the same time we also start working on some designs for the pcb version.

Screen Shot 2014-07-11 at 6.40.37 PM

 
1 http://www.silabs.com/products/clocksoscillators/pages/clockvsoscillatortutorial.aspx
2 CIRCADIAN RHYTHMS FROM MULTIPLE OSCILLATORS: LESSONS FROM DIVERSE ORGANISMS Deborah Bell-Pedersen, Vincent M. Cassone, David J. Earnest, Susan S. Golden, Paul E. Hardin, Terry L. Thomas, Mark J. Zoran Nat Rev Genet. Author manuscript; available in PMC 2009 September 1. Published in final edited form as: Nat Rev Genet. 2005 July; 6(7): 544–556. doi: 10.1038/nrg1633