The month of January continues with command stations working in their on-going recovery efforts of AMSAT OSCAR 40. The command team has determined the following:
* The V-band, U-band and the L-band (L1) receivers are working on the the high-gain antennas. The omni-directional antennas appear to be non-functional. The command team's conclusion is that damage has been sustained to the omni-directional antennas, antenna cables or antenna relays (or possibly all three).
* An attempt to command the V-band transmitter on the high-gain antennas has been done several times with no downlink signals detected. Telemetry may be indicating the transmitter is working, but with the current position of the satellite, V-band signals may not be receivable due to the assumption that the high-gain antennas may be pointing into space and not at Earth. Further tests will be conducted.
* No recent tests have been conducted on the U-band transmitter, but tests are planned once the current spin rate is reduced and the command team can confirm the heat pipes are working.
* The attitude control system is fully functional. Currently, a high spin rate (of about 17rpm) and an extreme sun angle (about 60 degrees) does not allow the sun sensor to provide accurate information. This explains why the indicated spin rate (via telemetry) is inaccurate. Without sun and attitude information the command team has suspended magnetorquing efforts, thus no further attitude or spin change has been attempted recently. Project leader DJ4ZC is developing a software algorithm which does not use sun sensor information. This software program will be tested and then used to try and reduce the spin rate and move the spacecraft to a better attitude.
In summary, once the sun angle and antenna pointing is improved, both the V-band and U-band transmitter tests can resume, along with suitable experiments of the ATOS (arc-jet) thruster and the momentum wheels.
ALON/ALAT is currently 248/-7, as listed on the AMSAT-DL web page.
Several stations, including AO-40 command station G3RUH have measured the frequency of the S-2 transmitter middle beacon as 2401.323 MHz. The beacon can be heard before perigee (between MA 245 and 256). Due to extremely high Doppler shift coupled with spin wobbling and fading, error-free telemetry reception will be difficult.
Moe Wheatley, AE4JY, has released an updated of his AO40RCV soundcard-demodulator. Data export and AFC have been improved, recorded sound files can be used and triggering up/down keys of (most common) transceivers for automatic doppler correction has been implemented. More information on AO40RCV is available at http://www.qsl.net/ae4jy
The current AO-40 orbital element set number 28:
Satellite: AO-40
Catalog number: 26609
Epoch time: 01018.53756618
Inclination: 5.9258 degrees
RA of node: 230.0726 degrees
Eccentricity: 0.8133560
Arg of perigee: 208.4998 degrees
Mean anomaly: 11.7742 degrees
Mean motion: 1.26922670 rev/day
Decay rate: -1.63e-06 rev/day^2
Epoch rev: 99
Checksum: 299
[ANS thanks AMSAT-DL and AMSAT-NA for this information]