Olin stopper:

1. Weave a circle round him thrice and close your eyes with holy dread ...

2. 10 year if possible zero cost zero space zero effort processor
mains fail data save and  shutdown energy source required with 100 -
1000 mJ  energy per event and operation from liquid nitrogen to liquid
lead temperatures, if possible*.

                                   * for as wide a range of 'if' as
Murphy allows.

3.  http://www.microsoft.com/nz/windows/internet-explorer/
     http://www.softpedia.com/get/Internet/E-mail/E-mail-Clients/Outlook-Ex=
press.shtml
     http://www.mozillamessaging.com/en-GB/thunderbird/
     http://www.opera.com/download/
     https://www.google.com/accounts/NewAccount?service=3Dmail&continue=3Dh=
ttp://mail.google.com/mail/e-11-80d8afb91ffe7d4bc84bbd89dfa03-4efeca503f1ac=
e397f7e72232691cfaf6c0f9bf5&type=3D2

>>   Storage time?
>     >=3D 600mS

I meant lifetime of storage system.
Let's say "years". [[ I now see "10 years' is / was mentioned. That
helps push the envelope.

Wet electrolytics will have the most severe difficulty reaching a 10
year spec, especially with a fuzzy % of elevated temperatures.
eg a 5000 hour cap (extreme) to last 10 x 8765 =3D 88,000 hours needs to
operate at a mean of log_2(88,000/5000)  x 10 degrees C or about 45 C
below its rated temperature.

ie a 105 C cap, 5000 hour at 60C.
A mere 2000 hour, 105 C cap needs to operate at say 55 below rated or
50C operating.

Hmm ...  that  spec is not TOO tough.
Note that running a wet electro at elevated temperatures WITHOUT
applied voltage is a more severe test.
If doing this with Al ecaps run at closish to rated Voltage. But, I'd
be wary of doing it.

I'd hope that a 3.3V rated processor would be specified to operate
somewhat below this - maybe not.
Ideally a Schottky drop below back voltage or say in the 2.5V - 3V range.
If it made a difference, MOSFETS like I mentioned recently (CES231x)
would allow about zero voltage drop in operation at a cost of under 5
cents per FET.
($US0.05 in NZ in 3000 quantity).

You can get very small 6V cells intended for some instruments, tiny
remote controls etc.
Also  a stack of 3 of the smallest available Alkaline "'coin cells"
would vastly exceed you energy requirements with shelf lives of say 5+
years.
 312 cell is 7.9mm dia x 3.6mm thick.
Probably good for 20 mAh in Alkaline if you can get them.
3 of these are ~=3D 200,000 mili.Joule new or many power failures, even
after a long shelf life.
(20 mAh x 3600 s/h x 3cells x 1.1V say =3D 237,600)
even a non-alkaline cell would suffice.

If available a 230 size Lithium at 5.9 mm dia x 3.6mm thick probably
manages around 15 mAh or about 150,000 mJ and a very long shelf life.

ie - a battery solution looks viable and attractive and potentially
reasonably priced.

Even much reduced battery capacity at extreme temperatures makes it
look likely that a battery solution is potentially viable.

_________

I've idly wondered  how a pager vibrator motor running a suitably
large flywheel would fare as a motor/generator on power off :-).
Hours are long. Magnetic bearing is easy enough and may even make such
a solution viable. Not one I'd expect to see anyone using though :-).




     Russell
--=20
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