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ups.com...
http://www.lazygranch.com/sound/shortwave/4814usb.wav

I recorded this from the SF Bay area in usb. It looks like bursts of
5Khz modulated at 500hz, then of course gated to wait for an echo.

BTW, I think this is codar.

Yeah, Codar seems likely.
I've put some plots from your recording at alt.binaries.alt.
There are some good echos there.
0.02 seconds corresponds to 6000 km.
I think you will find that the signal is sweeping
down from 4820 to 4790 over about 0.5 seconds,
repeating every second.
It is audible when it passes through the passband
of the receiver.

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rb