Modifying an oscillator circuit

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Flying Jester

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Hey.

Can someone help me out? I need to make a 5-20 Hz squarewave (ideally) oscillator. Not variable, but fixed anywhere between 5 and 20 Hz. I'd like to only use basic components--no ICs, no inductors; just capacitors, resistors and transistors.

I've found quit a few 2 Hz oscillators online (like the one on the left in the PDF I included). How can I change the circuit to speed up the oscillation?
 

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Simply change the RC time constants accordingly, either reduce all capacitances or resistors by a factor of ten.
 
Alright. I knew it wouldn't be difficult, but I wasn't quite sure how to proceed.

Also, I meant to say the RIGHT, not left.

Just considering my options here, how low power can a 555 operate on? And will it change the timing characteristics at the extrema?
 
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The CMOS version of 555 has a supply current demand in a 100 uA order of magnitude, so it can't compete with the low power transistor circuit. 555 is designed for up to MHz rate, so it needs a higher bias current. But the output will a clean rail-to-rail squarewave.
 

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