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Re: FO-29 status



Hi, All,

Here is a reply from the JARL who is responsible on FO-29 
operation.

--------------------------------
Current situation of the FO-29 is as following and regret but 
she is NOT in a condition to offer worldwide seivice.

1. Blance of Power budget
Although power from the solar cell is just adequate, inner 
impedance of the Ni-Cd rechargeable batteries is increasing.
Therefore approximately 10 minutes lator after the bird entered
eclipse, UVC will be activated and pull the trigger on the 
transmitter shut down.
Currently eclipse rate is about 33%.

2.The PCU (Power Control Unit) is in trouble and hence 
transmitter does not wake automatically up, even the voltage
at the battery terminal became high enough.

>From above mentioned situation, untill the bird obtain less than
25% of eclipse ratio, Max 20 minutes in Non-eclipse period and
10 minutes in eclipse period are operation limit in One day.

Now a days, bird passes over Tokyo 2-3 times in a day between
10:30hours to 14:00hours and in between 10-11hours, the bird
flys over the Pacific Ocean which brings very good result on 
commanding, just after the command station got AOS.
Then the bird passes Arctic area and serve to Scandinavia
and most of Europe area before the transmitter shut down 
by the  by UVC. ( Part of East Coast of North America
will also be in service area )
On the 12hours to 14hours passes, because bird flys over the
Continent, command does not reach to the bird.
Some time, control station can not turn the trasmitter on
by several reasons.
Even the bird waked up by command, service duration will
be much shorter.

As JARL, will take a care on FO-29 to serve for as many as 
possible users in the world, however, please do understand 
above reasons.
About 2 years lator (year 2010), FO-29 will has no-eclipse,
then it may be possible to operate for longer duration.

-----------------------------------------

73s
Toyo Komatsu,
JA0CQP 

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