The first signal was recorded on August 5 from 19:13 UTC till 19:21 UTC. The frequency was 2401 MHz and the mode was CW. The antenna is a 60cm dish with a 12 degree beam width pointed at an azimuth of 164 degrees and an elevation of 80 degrees (10.07 Ra, 40.7 Dec) The signal sounds like a PCM type digital modulation and a wave file sample link is below. A second signal was received using the same dish orientation on August 6 from 16:05 UTC till 16:16 UTC. This signal exhibits the same characteristics of the one from August 5. As of yet the source is unidentified but is likely an earth orbit satellite of some kind.
2401 MHz Unknown downlink sample
The screen captures below contain the following pieces of software used during the reception of the signals. Radio-SkyPipe a strip chart recoding program running on the bottom of the screen. It records the audio amplitude as seen by the computers internal soundcard. Spectrum Lab, an audio waveform analysis program displaying the audio waterfall spectrum of the sound card signal.. Radio-Eyes, a program which displays stellar radio sources, provides an indication of sky temperature and where the dish antenna is pointing in drift scan is shown on the middle left screen. SetiFox Doppler detector, a set of software programs developed to detect and record signals which exhibit Doppler shift due to the objects movement or the earths rotational motion is running on the center right side. What is seen is the Doppler data extractor showing the logged information on the received signal. The Doppler display central peak indicates the signals bandwidth, the two smaller side lobes indicate the +/- shift of the audio frequency in Hz/sec during the signals observed duration .
Click on images for a larger display.
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