Actually I think you are right. I believe that what is really needed is
to keep the egg at an average temperture of 99.5 over a period of say 10
minutes. I also know that if the egg goes over 103 it will kill the
embreyo almost instantly. I suspect that if I could keep it between 101
and 98 and average 99.5 it would work out well. There is also the fact
that the hen will leave the nest every day for about 10-15 minutes. In
some species of birds the male will sit the egs during this period. In
others the eggs are left to cool. I would suspect that during that
period the egg could cool 10 or more degrees. That is only once a day
though. It should also be noted that in those species that the eggs are
left to cool the eggs are well insulated with wood chips , grass, and
feather down. In the species where wher the male sets the eggs while the
hen is off the nest the nest iss essentually a hard surface and the
parents will throw out any thing that might insulate it.

RalphSnail Instruments wrote:
>
> <snip>
>
> >incubatotor that uses a micro controller that will maintain temperture with
> >in one degree farenhite
>
> Perhaps you can loosen your specifications on the temperature precission.
> The hens cannot achieve 1F stability and chicken still hatch.
>
> The temperature will also differ in different places inside the incubator
> unless you include a fan to equalize the temperature distribution.
>
> Josef
>
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