starman wrote:
"Eric F. Richards" wrote:
Soliloquy wrote:
"Macman" wrote in news:ifWdnVOu5OspPp3dRVn-
:
There still there. Now they have a reverb component to them, they kina
sound like a duck quacking. Odd thing is that they sound like mirror images
when listened to on USB versus LSB.
Strange, pulsating sounds.
In ISB it is one continuous sweep from one side of the center freq to
the other. Weird!
It's a CODAR station. It's a kind of shortwave radar. They transmitt a
sweeping HF signal, then listen for the return signal which is used to
determine ocean wave height far out to sea.
Yeah, that was essentially said, since
AFAIK there are no other OTHRs
operating these days. Putting it on a spectrum analyzer was
interesting -- the signal started at some frequency, say 4.785 + x,
and swept rapidly down to 4.785 - x. I'd be interested to know what
the sweep gains them in their imaging.
--
Eric F. Richards,
"Nature abhors a vacuum tube." -- J. R. Pierce, Bell Labs, c. 1940