[time-nuts] GPS chicken tracker (slightly OT but sorta-not-really)

[Magnus Danielson]

Bruce Griffiths wrote:
> Jim Palfreyman wrote:
>> A friend of mine has asked me for a good GPS method to find out where
>> his chickens are laying eggs.
>>
>> A GPS tracker comes to mind but some
>> (http://www.coolest-gadgets.com/20060405/really-cool-portable-gps-tracker) 
>>
>>   seem good but expensive.
>>
>> Does anyone have any cheap (and possibly smaller) alternatives?
>>
>> Regards,
>>
>> Jim Palfreyman
>>
>>    
> Turn the problem on its head and fix a transmitter to each chicken.
> One can then use range measurements from several antennas to track the 
> chickens, just assign a unique PRBS code to each transmitter.
> You should be able to do all this with a SDR and some software.
> This is likely to be cheaper per chicken than using a GPS tracker.

You can reduce wading through data by identifying when the chicken is 
more or less fixed for sufficient time to lay the egg. Your friend will 
know very well what kind of time-span it is.

Instead of transmitting CW, it is sufficient if it gives a single beep 
once in a while. A simple receiver could allow for addressing and then 
trigger the beep. Possibly could 1-wire ID tags be used for the "high 
end logic".

Regardless, I think part of the problem would be just to find a chicken 
and keeper friendly way of attaching these things to the chicken, recall 
that they need recharging and eventually battery replacement.

I wonder if not his problem could be solve by much simpler low-tech 
solutions to steer the chicken to lay the eggs at some more suitable 
spot for both them and the keeper.

Cheers,
Magnus