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Author Topic: What is this signal?  (Read 1452 times)

Offline Dag

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What is this signal?
« on: July 19, 2014, 0500 UTC »
Please listen to the short 9 second audio clip. What is that signal?

I've heard this sound for years. This one was recorded on 7657 khz, but it occurs all over the HF spectrum I think.

One thing about this particular recording is that the tone changes slightly with each burst -- something I've not noticed before.

Dag
Seminole county, Florida, USA, Earth, Solar System, Universe.Icom 7610 + attic dipole. Black coffee. Ketosis.

Offline ka1iic

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Re: What is this signal?
« Reply #1 on: July 19, 2014, 1637 UTC »
Sorry I can't tell you what it is but I have wondered what it is since the 1970's when I first noticed it myself... sounds like using sand-paper kinda sorta...

Maybe someone else on the board knows what it is....
73 Vince
KA1IIC

"If you can't be anything, you can at least be annoying"

Troy, Ohio. 20m Vertical & low long wire E/W, Yaesu FT-187ND, SDRplay 2, Ratt Shack 2 meter rig, and other little bits of electronics I'm not talking about, homebrewed and otherwise... so there bleech!

Offline Token

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Re: What is this signal?
« Reply #2 on: July 19, 2014, 1759 UTC »
This is the Panther-H Frequency Hopping system, there are 8 pulses in the SOC (you appear to have captured the last few of the 8).

T!
T!
Mojave Desert, California USA

 

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