FO-29

FO-29 status 7 Aug 2007

Forward Message from JARL
Translated by Mineo Wakita, JE9PEL
23 Apr 2007

An analog transponder of a amateur radio satellite "Fuji-3"
stops now. We ask for an offer of the information for
investigation and restoration of a cause.

Orbiting amateur satellite "Fuji-3" (FO-29, 8J1JCS) of JARL
performed a consecutive use of regular analog system, but we
confirmed the analog transponder which we should have been
managing on 21 April 2007 stopped.

We apply it to the investigation of a cause in a control station
and collect the information and analyze the telemetry before
a transponder stops now. And we draw up a command plan toward
the future restoration. As for the station having the following
information about "Fuji-3", we wish to does an offer of these
information in JARL Development Section.

-----------------------------------------------------------------
CW telemetry data after 07:00(UTC) April 20, 2007
Tranaponder movement situation after 07:00(UTC) April 20, 2007
(CW telemetry is a stop, but a transponder can work.)
If there is a phenomenon, in addition, to become reference,
please send to us the signal strength or the reception situation.
-----------------------------------------------------------------

We ask for cooperation of people for restoration of "Fuji-3".

An information destination: lab (at) jarl.or.jp



FO-29 Operation Pause (Fwd from JARL)
Translated by Mineo Wakita, JE9PEL
5 May 2005

About "Fuji-3" Present Condition and Operation:
(Although the normal operation is checked, the operation is
 stopped for a while.)

It is as a previous report an amateur satellite "Fuji-3"
(JAS-2, FO-29, 8J1JCS) of JARL. From 21 April, 2007, although
the analog system transponder had stopped, we announce you
the subsequent present condition.

On 3 May, Thu. 16:00 (UTC),
We could check an analog system transponder (JTA) of "Fuji-3"
was worked to ON and OFF by command from a GS control office
and there was no fault in a command system.

On 4 May, Fri., we made turn ON the analog system transponder,
and the electric power income and outgo were checked. The rate
of the shade was 25%, so the electric power income and outgo
turned out that it is in a quite severe state.

Since the check of the electric power income and outgo, the
battery reconditioning, etc. are worked, we do as stopping
the operation of "Fuji-3" for a while. Although we cause users
much anxiety, we consent-wish-do.

In addition, although it may turn ON temporarily an analog
system transponder over Japan during an operation dormant period,
please refrain from use of transponder such as a loop test
and a communication.



JARL report about FO-29 (Fuji-3) power status
Translated by Mineo Wakita, JE9PEL
7 Aug 2007

The internal impedance of the battery in FO-29 (Fuji-3) is now rising
extremely due to the deterioration caused by almost 12 years in orbit..

According to the telemetry data a 25 minute eclipse duration is estimated
as a limit as for the analog battery system use. Because the eclipse
length of FO-29 (Fuji-3) is currently about 30% or almost 32 minutes,
the power supply of the relay with the battery cannot serve a period of
the eclipse.

A malfunction also occurs in part of the electricity control system.
The malfunction is the UVC which is an automatic function for electricity
management. When the satellite is in the eclipse, and the light of the sun
is not the solar battery, the transmitter is turned OFF by the UVC.

It is designed so that later an analog system transmitter becomes ON
automatically when the terminal voltages of the battery exceed a set value
after the power is available from the solar battery. However, it appears
likely that a malfunction occurs for this function, and the terminal
voltage cannot turn on a transmitter even if it exceeds the set value
unless commanded from the ground.

The length of eclipses for FO-29 (Fuji-3) will rise in future and rises
to 34% in March 2008 and comes over a peak of the eclipse duration.
When it goes over this peak, the eclipses will decrease slowly, and drop
to 20% in August 2009. By February 2010 it is all sunshine with no eclipses
for about 8 months. It seems that we can apply the analog system relay
consecutively for this period.
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