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Re: UO-36 over S.America?



on 4/2/00 11:51 PM, Jim Walls at k6ccc@earthlink.net wrote:

>> AO-10 is a great bird, but I don't think we are supposed to follow its power
>> budgeting scheme.
>> 
> 
> Remember Jon that AO-10 has been in orbit almost 14 years past the end of it's
> projected lifetime.  The CPU that controls it failed well over a decade ago,
> and the batteries are dead.  We are lucky that when the bird gets into
> sunlight for a while it powers back up in an operational state at all.  This
> is not a "power budgeting" issue.  How well would the batteries on your
> handheld be working after after 17 years?  Answer, they would be just like
> AO-10's, they would be absolutely flat DEAD!  We are lucky that they failed
> open and not shorted so at least the satellite has a chance to operate when
> it's in sunlight.

I don't need an explanation of AO-10's problems.  It was a tongue in cheek
remark.

> 
>> Why do we do this?  Let's see we have AO-27, KO-25, UO-36, SO-35 and who
>> knows what else.  All have power budget issues.  Where are we missing it
>> design wise?
>> 
>> OK, OK, so AO-27 and SO-35 have other payloads that take precedence, but it
>> still doesn't eliminate the problem of not enough power budget for normal
>> operations.
>> 
> 
> I think Jon needs to get involved in a group building a satellite and learn
> more about compromises required when designing a satellite.


That's it: compromise.  We compromise and we put up hardware that ends up
not working or not working properly.  And it makes amateur satellite
operators look silly to the rest of the ham radio world and hence people
stay away.  I did for a long time.

I am stepping way over the line of political correctness and I'll probably
get branded and not worked on the birds, but who cares.

The recent success rate of the JAWSAT platform shows how well compromises
work when building satellites.  Hopefully we are learning from that
experience.

Fortunately, it looks like the P3D team DIDN'T compromise in its design.


73,

Jon
KE9NA 

-------------------------------------
Jon Ogden KE9NA

Member:  ARRL, AMSAT, DXCC, NRA

http://www.qsl.net/ke9na

"A life lived in fear is a life half lived."

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