[amsat-bb] FO-29 Status

Yutaka Murata yutaka.murata at nifty.ne.jp
Mon Sep 7 06:01:57 PDT 2009

Hi FO-29 Guys

This is FO-29 status from JARL command team.
This was written in Japanese and I translated to English.

FO-29 status in 2009

FO-29 launched in August 1996 and has been working 14 years.

FO-29 is planning to operate the consecutive use with the analog 
transponder until the end of August 2009, but it was confirmed that a 
transponder stopped on August 25.

In the later pass, the transponder operation is confirmed when we sent a 
command of transponder ON from the control station, but we stopped 
transponder temporarily now.

We had the a similar symptom of stopping the transponder in the spring 
of 2007 .

FO-29 is in the "high shade rate period" now.
Both of the transponder stop in the spring of 2007 and this time are 
thought that by this "high shade rate" and by the rise of the internal 
resistance of the deterioration of the battery and by the influence of 
the temperature of the battery.

The power control system FO-29 (PCU) watches a terminal voltage of the 
battery and turns off the power supply of the transmitter automatically 
if it becomes less than the setting voltage. In addition, When FO-29 
enters the sunshine area and it recovers to the setting voltage by sun 
battery power, it is designed to turn on a transmitter automatically.
However malfunction occurred for this function in 2007.

Because of transmitter was not turned on automatically, We made an 
operation schedule plan from the summer of 2007 and managed 1-2 times on 
in a day.
This  management operation worked well. The electricity income and 
expenditure restored or it was cured spontaneously.The transponder has 
been worked without control command from control station from summer of 

The power supply circumstances of current FO-29 is almost same situation 
as stop period spring of 2007, scheduled operation period, the 
consecutively operative period from the summer of 2008 and it is in a 
"high shade rate". This transponder off is supposed to be a similar 
situation as when transponder stopped in the spring of 2007.

 From this , We decided that we make the operation schedule plan, and 
manage the limit of the operative number of times in one day like last 
time to keep the electricity income and expenditure  untill improve the 
"shade rate" which is in January, 2010.

Thanks control team

JA1COU  Yutaka Murata

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