feb 19 2004
Vi kan lsa fljande p AMSAT-DLs hemsida:
Parkes 64m Radio Telescope Listens for AO-40
With our attempts to restore AO-40 we have received today significant support from Parkes Observatory in Australia. http://www.parkes.atnf.csiro.au/
The Parkes Observatory is operated by the Australia Telescope National Facility (ATNF) which is part of Commonwealth Scientific and Industrial Research Organisation (CSIRO).
From here were received the live pictures of Apollo 11 Moon landing, 1969. See above homepage of Parkes.
The radiotelescope has a diameter of 64 metres and the system noise figure is approx. 25 K.
From about 6:00 UTC, a 4 MHz wide spectrum with center frequency of 1097 MHz was scanned with high level technique in order to find the LO frequency of the AO-40 L1 receiver. A band of approx. +/- 20 kHz around the actual LO frequency was examined intensively. Three hours were needed to prepare the setup for AO-40 and to search.
Unfortunately nothing was heard which could be a signal of AO-40!!
The fact that nothing was heard of the L1 receiver s LO does not lead to the conclusion that AO-40 is completely dead. The receivers of Parkes are not really fitted for frequencies below 1.25 GHz, and naturally one does not know how good the L1 receiver s LO is shielded or how much of the signal would go through the antenna to the outside world. During the next days more research follows.
The L1 command receiver is continuously switched on, and it would have been good news if we had such a confirmation that the 10 V power source for the L1 receivers is still functioning. All receivers and also the IHU are supplied with the 10 V source.
All command stations are continuing to send commands to the satellite in order to switch the batteries.
I would like to say a great thank you on behalf of AMSAT-DL to Brett Dawson, VK2CBD and the team of Parkes observatory, especially to Dr. John Reynolds (Officer in Charge) and John Sarkissian (Operations Scientist).
Peter Guelzow, DB2OS