[X] My Assistant

[djellison]

Random thought. I was just sent an interesting movie, which was a composite of various space stills, with some plasma/wave sounds in the background and a generic 'beep beep' spacecraft noise on top.

But what do spacecraft actually sound like when transmitting - has anyone heard the 'feed' from a DSN dish be deconstructed into an audible wav? Is it like a dial up modem or something else. Do spacecraft at 288kbps sound different to those at 120bps etc? I'm not talking about the spooky interpretations of mag/fields/waves/particles etc that we are treated to - but the actual downlink itself. The only example I can think of is the MEX cannister mode listening to PHX during EDL - but that actually ended up like a plasma/wave observation because of the massive doppler involved!

I remember the BBC 'The Planets' series ( very good, spectacular visuals, but now very out-dated ) - and every time a spacecraft flew past the camera, it made a beautifully doppler shifted 'beep beep beep' sound.

Doug

[Astro0]

Hmmm. You've got me thinking there Doug.
I will try and get down to the Operations Centre later today....the link operator tells me that you hear a variety of sounds as the antenna tracks and locks onto the signal....Astro0

EDIT: OK, here's a recording coming off the spectrum analyser I took this evening as we were commencing a tracking pass. Sorry, I've had to cover up the frequency being used for this spacecraft. It starts out as white noise, then as the carrier signal comes in you can here the pitch changing. Then some warbling noise as the system locks in. This is just the carrier, the data itself is at a higher rate and off the scale for hearing through the speakers. It'd just be noise anyway I'm told. Interesting all the same.
 spacecraft_sound.wmv ( 413.11K ) Number of downloads: 809