PA3GUO SEEDS II Experiments
CubeSat was advocated by the Prof. Twiggs at the Stanford university in USSS(University Space System Symposium) in 1998.
Then, Nihon University starts the development of CubeSat in 1999, and the research and development has been advanced.
The knowhow of the development of CubeSat was acquired by developing a mock satellite "CanSat" which autonomous flies from the high degree 4000m to the destination at the first year of development.
The simulation of SEEDS operation is ended on June 14, 2005.And, SEEDS was launched on July 26, 2006. Unfortunately, the launch was failed becouse of rocket's engine trouble.
We developed 2nd SEEDS after failure. And 2nd SEEDS was launched from Satish Dhawan Space Center, India in April 28th 2008.
source: SEEDS website (see below)
SEEDS Project website
Frequency 437.485 MHz
Frequency deviation plus minus 1750 Hz
CW transmission power 90 mW
FM transmission power 450 mW
July, 06, 2008
July, 01, 2008
20:35utc
Very strong downlink, noise-free !
June 12, 2008
May 03, 2008
April 29, 2008
Observed SEEDS-II during a pass with an maximum elevation of 90 degrees.
Signal was very clear and strong, with slow variation due to rotation.
Equipment: TS2000X, 2x8 element beam, no pre-amp.
At only 1.0 degrees elevation the downlink signal was still well audible, 20 dB above noise:
11:15utc
Recorded SEEDS at the very end of a pass, and discovered it was in 1k2 FM packet mode.
Frequency 437.485 MHz. Antenna: 2x8 element beam, no pre-amp.
SEEDS-II FM Packet 1k2 mp3 recording (12 seconds)
JQ1YGU*>JQ1YGV
89 degrees elevation pass, 437.485 MHz, SEEDS back into CW:
...b07af8aedb3b1100000001000100018d7a304030
jq1ygu seeds g40348ddc1d87ffe008007000000dc421cb15af8afbb461100000001000100018d7b304030
jq1ygu seeds g40348e1a9d38ffe9a3000000000a63008b1daf3b07b4c1100000001000100018d7c304034
jq1ygu seeds ...
Recorded SEEDS at the very end of a pass, from 9 to 4 degrees elevation.
Satellite was in digitalker mode, and transmitted, amongst others, the 'secret code' and SSTV picture.
Both samples I submitted on the SEEDS website in order qualify and receive the QSL cards.
mp3 recording of the SEEDS digitalker 'secret' code
ps:this recording has been edited: the code is recoded, else it wouldn't be secret anymore :-)
SEEDS has for the second day been put in FM mode. Transmissions consist of speech
and SSTV signals. At the bottom of the images the callsign (JQ1YGU) is due to the noise
barely visible, but present.
mp3 recording of the FM transmission of SEEDS: Speech (text) + SSTV (image)
 
CW telemetry recording of SEEDS
seeds g4 0013eealb8 ffe 007 ...
... .06 000 000 008 ed0 aa0 aa0 aa5 b07 1 1 0000 0001 0001 0001 0b76 0640 34
jq1ygu seeds g4 0014eti.ab ffe 007 12c 000
April 28, 2008
Satellite launched.