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Author Topic: What is this signal?  (Read 893 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.
TS440s + attic dipole.

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

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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