FO-29 sun angle
Subject: FO-29 sun angle
From: Mike Rupprecht
To: Mineo Wakita
Date: Wed, 25 Mar 2009 22:48:11 +0100
Dear Mineo,
Attached you can see a graph with the sun angle (deg) and illumination
(percent) for the next 60 days.
You can see that the sun angle is changing 2-3 deg per day. The signmeans
that the sun is shining from the left or from the right side of theaxis.
0 deg means the best angle -> the light hits with 90 deg on the solarcells.
FO-29 is always sending '72' for her sun angle. I am not sure if we can
trust this value.
If you need actually CW telemetry data ? please take a look on mySatBlog...
73, Mike
Subject: FO-29 sun angle
From: Mike Rupprecht
To: john heath, Mineo Wakita
Date: Fri, 27 Mar 2009 21:59:29 +0100
Hi John, Mineo
I read a lot about the sun angle calculation and found some information on
the Japanese JAS-2 website.
@ John: here is the English translation link
http://translate.google.de/translate?u=http%3A%2F%2Fwww.jarl.or.jp%2FJapanese%2F3_Fuji%2F&sl=ja&tl=en&hl=de&ie=UTF-8> &sl=ja&tl=en&hl=de&ie=UTF-8
FO-29 is calculating the sun angle to the Z-axis. My calculations based on
the angle between sun and the X-Axis !
BUT - Compass is sending always the channel 3B value &H24 -> that means
0100100 and correspond with 82.5 deg
You have to subtract 10 deg from the sent value because the Sun Sensor is
inclined with 10 deg
So we have an "real" sun angle of 72.5 deg. Compared with old telemetry
values this angle is constant since 2007!
Yesterday I wrote you that my calculations are showing a change of this
value of 1-2 deg /day. The actually value for today is -48 deg.
If we subtract 90 deg - 48 deg we get 42 deg. This is the angle I would
expect from FO-29.
It's all pretty strange. I think we come to a dead end..
Have a nice weekend !
best 73,
Mike
Code deg : Code deg : Code deg : Code deg
0000001 27.5 : 0110001 59.5 : 1100001 91.5 : 1010001 123.5
0000011 28.5 : 0110011 60.5 : 1100011 92.5 : 1010011 124.5
0000010 29.5 : 0110010 61.5 : 1100010 93.5 : 1010010 125.5
0000110 30.5 : 0110110 62.5 : 1100110 94.5 : 1010110 126.5
0000111 31.5 : 0110111 63.5 : 1100111 95.5 : 1010111 127.5
0000101 32.5 : 0110101 64.5 : 1100101 96.5 : 1010101 128.5
0000100 33.5 : 0110100 65.5 : 1100100 97.5 : 1010100 129.5
0001100 34.5 : 0111100 66.5 : 1101100 98.5 : 1011100 130.5
0001101 35.5 : 0111101 67.5 : 1101101 99.5 : 1011101 131.5
0001111 36.5 : 0111111 68.5 : 1101111 100.5 : 1011111 132.5
0001110 37.5 : 0111110 69.5 : 1101110 101.5 : 1011110 133.5
0001010 38.5 : 0111010 70.5 : 1101010 102.5 : 1011010 134.5
0001011 39.5 : 0111011 71.5 : 1101011 103.5 : 1011011 135.5
0001001 40.5 : 0111001 72.5 : 1101001 104.5 : 1011001 136.5
0001000 41.5 : 0111000 73.5 : 1101000 105.5 : 1011000 137.5
0011000 42.5 : 0101000 74.5 : 1111000 106.5 : 1001000 138.5
0011001 43.5 : 0101001 75.5 : 1111001 107.5 : 1001001 139.5
0011011 44.5 : 0101011 76.5 : 1111011 108.5 : 1001011 140.5
0011010 45.5 : 0101010 77.5 : 1111010 109.5 : 1001010 141.5
0011110 46.5 : 0101110 78.5 : 1111110 110.5 : 1001110 142.5
0011111 47.5 : 0101111 79.5 : 1111111 111.5 : 1001111 143.5
0011101 48.5 : 0101101 80.5 : 1111101 112.5 : 1001101 144.5
0011100 49.5 : 0101100 81.5 : 1111100 113.5 : 1001100 145.5
0010100 50.5 : 0100100 82.5 : 1110100 114.5 : 1000100 146.5
0010101 51.5 : 0100101 83.5 : 1110101 115.5 : 1000101 147.5
0010111 52.5 : 0100111 84.5 : 1110111 116.5 : 1000111 148.5
0010110 53.5 : 0100110 85.5 : 1110110 117.5 : 1000110 149.5
0010010 54.5 : 0100010 86.5 : 1110010 118.5 : 1000010 150.5
0010011 55.5 : 0100011 87.5 : 1110011 119.5 : 1000011 151.5
0010001 56.5 : 0100001 88.5 : 1110001 120.5 : 1000001 152.5
0010000 57.5 : 0100000 89.5 : 1110000 121.5 : 1000000 153.5
0110000 58.5 : 1100000 90.5 : 101000 122.5 : --- ---
Hi Mike,
Thanks for a most interesting piece of analysis.
did you copy it to Mineo? He may know if there is a problem with FO-29's
telemetry value for sun angle.
73
John G7HIA
Subject: Re: FO-29 sun angle
From: Mineo Wakita
To: Mike Rupprecht
Cc: john heath
Date: Sat, 28 Mar 2009 08:36:53 +0900
Hello Mike, John
Please refer my_web,
http://www.ne.jp/asahi/hamradio/je9pel/fo29tlme.htm
http://www.ne.jp/asahi/hamradio/je9pel/fo29cwfe.htm
http://www.ne.jp/asahi/hamradio/je9pel/fo29cwth.htm
Thank you.
JE9PEL, Mineo Wakita
Subject: FO-29 sun angle II
From: Mike Rupprecht
To: Mineo Wakita
Date: Mon, 30 Mar 2009 09:48:44 +0200
Dear Mineo,
another strange issue:
If you read the decoding of the CW telemetry from the following Japanese
side :
http://www.jarl.or.jp/Japanese/3_Fuji/teleme/tlm.htm
You will find an value for channel 3B -> 42. This is 0100 0010 and according
the table we get an sun angle of 150.5 deg.
If you see the decoded value from this site - they get an sun angle of 40.5 deg.
Why ???
Maybe you can understand this.
Best 73 and domo arigato,
Mike
Subject: Re: FO-29 sun angle II
From: Mineo Wakita
To: Mike Rupprecht
Date: Tue, 31 Mar 2009 12:48:03 +0900
The value 40.5 is wrong, the value 140.5 is right,
so the value in the web site is wrong.
Sun Angle is an angle from the X-axises of the body coordinate of
the satellites.
Because a sensor is set at the angle that inclined 10 degrees,
it is necessary to subtract 10 degrees from the value in the web site.
42 -> 0100 0010 -> 150.5 in the table -> 150.5-10=140.5 deg (is right)
Please see,
http://www.ne.jp/asahi/hamradio/je9pel/fo29cwfe.htm
My fo29cwte.exe can calculate the valid Sun Angle.
http://www.ne.jp/asahi/hamradio/je9pel/fo29cwte.zip
JE9PEL, Mineo Wakita
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