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Author Topic: 13100 +/- Khz mystery signal  (Read 530 times)

Offline NM8R

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13100 +/- Khz mystery signal
« on: March 28, 2024, 2051 UTC »
For the last 2 days I've been hearing an unusual signal around 13.100 MHz.  I've had limited success demodulating it.  I can only recover audio using FM.  It is distorted and appears to be over modulated.  However, the waveform does not look like an FM signal on my SDR. 

It sounds like a female voice, perhaps in Spanish, playing a short repetitious loop that seems like it would be appropriate in a casino at some type of gaming machine.  Think in terms of a repetitive loop to capture the attention of passers by.

It drifts from 13099 to 13114 kHz. 

My QTH is Northern Michigan. I haven't yet been able to observe its propagation outside of daylight hours, but will this evening.

At the time of this writing, 2030 UTC, it is at -85 dBm.  I'm using a Perseus, in combination with a 35' LNV with a transimpedance amplifier at its base.

Someone will no doubt ask, so be advised, it is not the aeronautical mobile weather service transmitting in sideband a few kHz lower.

If anyone else is able to hear this signal, I would appreciate your observations and input.

Scott




Offline NM8R

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Re: 13100 +/- Khz mystery signal
« Reply #1 on: March 28, 2024, 2107 UTC »
Another data point: I just now found it also on 13.685 MHz, with identical programming.  Slightly weaker on this frequency, but the same audio feed.

Scott

Offline Token

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Re: 13100 +/- Khz mystery signal
« Reply #2 on: March 31, 2024, 2139 UTC »
Recording?  Screenshot?

What you are describing is pretty open to interpretation.  Since you posted I have left a receiver on the frequency, so far have not heard the signal.

T!
T!
Mojave Desert, California USA