[amsat-bb] Re: FO-29 status

Auke de Jong, VE6PWN sparkycivic at shaw.ca
Sun Jan 20 19:43:26 PST 2008

I don't fully understand what you mean by "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".  Does this mean that the 
satellite can only run for one pass over Japan each day, even if it has 
coverage for many passes?  Does this also mean that activating the satellite 
more than once in a single day might cause harm somehow?

I dont' want to seem snoopy, I just don't like to see a useful satellite 
being un-used just because it needs to be woken-up by somebody who knows the 
"secret" codes ;)


----- Original Message ----- 
From: "JA0CQP" <ja0cqp at po30.lcv.ne.jp>
To: <amsat-bb at amsat.org>
Sent: Sunday, January 20, 2008 6:17 PM
Subject: [amsat-bb] 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,
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
> -- 
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.5.516 / Virus Database: 269.19.7/1234 - Release Date: 1/20/2008 
> 2:15 PM

More information about the AMSAT-BB mailing list