There are numerous radars running in the HF bands.
Some of them run continuously.

Frequencies heard in San Diego.
4407
4814
12180 to 12100
13370 to 13450
13500 to 13570
13920 to 13970
26340 to 26190

We can examine their echos too.
I recorded the one at 26190 (a while back) for 60
seconds and ran an autocorrelation.
A plot of it is posted in alt.binaries.alt.
We can see that it echos over great distances,
on the order of the circumferance of the Earth.
(The horizontal scale is time converted to distance
figuring the signal travels at the speed of light.)

--
rb

"Ron Baker, Pluralitas!" wrote in message
...
There are numerous radars running in the HF bands.
Some of them run continuously.

Frequencies heard in San Diego.
4407
4814
12180 to 12100
13370 to 13450
13500 to 13570
13920 to 13970
26340 to 26190

We can examine their echos too.
I recorded the one at 26190 (a while back) for 60
seconds and ran an autocorrelation.
A plot of it is posted in alt.binaries.alt.
We can see that it echos over great distances,
on the order of the circumferance of the Earth.
(The horizontal scale is time converted to distance
figuring the signal travels at the speed of light.)

--
rb

"Ron Baker, Pluralitas!" wrote in message
...

"Ron Baker, Pluralitas!" wrote in message
...
There are numerous radars running in the HF bands.
Some of them run continuously.

Frequencies heard in San Diego.
4407
4814
12180 to 12100
13370 to 13450
13500 to 13570
13920 to 13970
26340 to 26190

We can examine their echos too.
I recorded the one at 26190 (a while back) for 60
seconds and ran an autocorrelation.
A plot of it is posted in alt.binaries.alt.
We can see that it echos over great distances,
on the order of the circumferance of the Earth.
(The horizontal scale is time converted to distance
figuring the signal travels at the speed of light.)

Any chance of posting a .WAV file? Like to hear what they sound like.

HankG

"HankG" wrote in message
...

"Ron Baker, Pluralitas!" wrote in message
...

"Ron Baker, Pluralitas!" wrote in message
...
There are numerous radars running in the HF bands.
Some of them run continuously.

Frequencies heard in San Diego.
4407
4814
12180 to 12100
13370 to 13450
13500 to 13570
13920 to 13970
26340 to 26190

We can examine their echos too.
I recorded the one at 26190 (a while back) for 60
seconds and ran an autocorrelation.
A plot of it is posted in alt.binaries.alt.
We can see that it echos over great distances,
on the order of the circumferance of the Earth.
(The horizontal scale is time converted to distance
figuring the signal travels at the speed of light.)

Any chance of posting a .WAV file? Like to hear what they sound like.

HankG

I've posted a couple to alt.binaries.alt.

Do you have a receiver?

--
rb

y'all like that Stupid Commie google so much,,,, do a search for,Wav
Format Scotland Music

MacMurphy's Braes are Bonnieeeee,,,,,, wherever faes the dew,,,,,,,
cuhulin

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.
Ron Baker, Pluralitas! wrote:
There are numerous radars running in the HF bands.
Some of them run continuously.

Frequencies heard in San Diego.
4407
4814
12180 to 12100
13370 to 13450
13500 to 13570
13920 to 13970
26340 to 26190

We can examine their echos too.
I recorded the one at 26190 (a while back) for 60
seconds and ran an autocorrelation.
A plot of it is posted in alt.binaries.alt.
We can see that it echos over great distances,
on the order of the circumferance of the Earth.
(The horizontal scale is time converted to distance
figuring the signal travels at the speed of light.)

--
rb

wrote in message
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.

--
rb

Interesting. Is there a canned program to take an autocorrelation of a
wav file? I noticed the signal was wide, so I used the 9.5Khz filter,
though clearly that isn't enough if the signal is 30Khz wide. BTW, it
has an interesting sound with FM demod.

I suppose if I had the ability to digitize at a higher bandwidth, I
could sample my 455Khz IF output and get the whole sweep. I did move
the VCO around a bit and couldn't find a center of the signal.

I've been looking at various high speed digitizers for use as a
pan-adapter. This is the most interesting of the bunch:
http://www.universal-radio.com/catal...rxvr/0014.html


Ron Baker, Pluralitas! wrote:
wrote in message
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.

--
rb

What!!!??? No over the horizon Radar!
There's that Johnny Cash movie commercial on my DirecTV Radio thangy
gin.

The tasteeee of lovee is sweetttt,,,,,,,
cuhulin