Help a kiwi -something supplys power from the batteries in an erratic timing

Thread Starter

Nz noob

Joined Nov 18, 2016
11
Hi there. I'm from New Zealand.

I work in conservation over and have been inventing a better way to encourage the animals that predate kiwi(a rare flightless bird on found in NZ), to enter the many traps we set for them.
My design requires a circuit if some sort that supplys power from the batteries in an erratic timing. So say 1sec on,3off,4on,1off,6on,6off 10on.
I'm sure this is simple but my attempts to learn electronics when I know nothing prior has led me here in the hope you guys might be to help me.

Anyone have any great ideas
 

Dodgydave

Joined Jun 22, 2012
10,063
A microcontroller is best design for this, like a Pic or Arduino, it can be done with timer chips like 556, cd4060, cd4040, but will be more complex. What voltages are you using?
 

Thread Starter

Nz noob

Joined Nov 18, 2016
11
A microcontroller is best design for this, like a Pic or Arduino, it can be done with timer chips like 556, cd4060, cd4040, but will be more complex. What voltages are you using?
I was hoping to keep power usage low and size small so probably an as size battery. So maybe 1.5v?
 

#12

Joined Nov 30, 2010
18,223
As soon as you want more than 2 or 3 time constants, a microprocessor is the way to go. I could do this in analog, but it would be the size of a cell phone and eat way too much current.

I guess I better shut up now. There's already two good suggestions quicker than I can type.
Just keep those 6 foot birds at your place. K? Thnx.:)

ps, there is a battery called A123. 12V and the size of a AA battery.
 

MaxHeadRoom

Joined Jul 18, 2013
23,810
Hi there. I'm from New Zealand.

I work in conservation over and have been inventing a better way to encourage the animals that predate kiwi(a rare flightless bird on found in NZ), to enter the many traps we set for them.
Isn't that called Evolution? Survival of the fittest?:p
You don't mention what you want to do with the device?

Just keep those 6 foot birds at your place. K?
.
I think they are called Emu's!:D
Max.
 

MaxHeadRoom

Joined Jul 18, 2013
23,810
Just part of the advice I was given on visiting down under is if you do a walk-about, carry a stick and don't poke you hand in any opening, fissure or gap in the terrain.
Max.
 

Thread Starter

Nz noob

Joined Nov 18, 2016
11
Yeah kiwis are smallish. Could ft high. Pretty good at striking with their feet. As for evolution. Nz was cut off from the test of the world and evolved its on unique species. Unfortunately humans released stoats,weasels,ferrets and if course cats.
My little invention basically acts like the feather being twitched for a pet cat. Predators then want to have a go at it and enter our kill traps that kill them instantly. Unfortunately it needs the erraticness.
 

Thread Starter

Nz noob

Joined Nov 18, 2016
11
Yeah kiwis are smallish. Could ft high. Pretty good at striking with their feet. As for evolution. Nz was cut off from the test of the world and evolved its on unique species. Unfortunately humans released stoats,weasels,ferrets and if course cats.
My little invention basically acts like the feather being twitched for a pet cat. Predators then want to have a go at it and enter our kill traps that kill them instantly. Unfortunately it needs the erraticness.
Sorry my English is fine but my stupid autocorrect made that post a bit weird :)
 

crutschow

Joined Mar 14, 2008
27,967
Below is the LTspice simulation of a 16-bit linear feedback shift register.
The one second clock V2 could be generated by a 555 timer configured as an astable multivibrator.
The circuit could also have been done with CD4000 series devices, but I didn't have the shift-register models of those in my library.
Is that sort of the random sequence you want?


upload_2016-11-18_14-28-40.png
 

Thread Starter

Nz noob

Joined Nov 18, 2016
11
Below is the LTspice simulation of a 16-bit linear feedback shift register.
The one second clock V2 could be generated by a 555 timer configured as an astable multivibrator.
The circuit could also have been done with CD4000 series devices, but I didn't have the shift-register models of those in my library.
Is that sort of the random sequence you want?


View attachment 115546
That looks like the business. The loop doesn't have to be very long. Just a few changes to remove unnatural regularity.
 

AnalogKid

Joined Aug 1, 2013
9,410
What is the purpose of the circuit? It seems you want to turn something on and off pseudo-randomly. What is that thing, and how is it powered? Also, what would be the minimum and maximum on and/or off times?

ak
 

Thread Starter

Nz noob

Joined Nov 18, 2016
11
What is the purpose of the circuit? It seems you want to turn something on and off pseudo-randomly. What is that thing, and how is it powered? Also, what would be the minimum and maximum on and/or off times?

ak
It will be powering an electro magnet to bring a pendulum back and forth. Magnets seem the best way to conserve energy.
 

crutschow

Joined Mar 14, 2008
27,967
That looks like the business. The loop doesn't have to be very long. Just a few changes to remove unnatural regularity.
Okay.
Here's the circuit with one 8-bit shift register and two inverter gates used to form a 1Hz multivibrator clock.
You could use a 74C164 in place of the 74HC164 since you don't need the speed of the HC device.
Also if you use the C device you can operate the circuit at any voltage between 3V to 15V.
The complete circuit should draw less than a 100 microamps of power.

upload_2016-11-18_17-3-14.png
 
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