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Author Topic: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18  (Read 2632 times)

Offline Lory

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Hello,
on summer nights I hear melodies from many years, probably via propagation.
An exammple received 17-8-2019 2300z at this link:
https://www.youtube.com/watch?v=saNHkouMLkk

Does anyone know who transmits them? What is it for?
Thank's

MOD EDIT: added frequency/channel to title for searching and archival purposes
« Last Edit: August 21, 2019, 1956 UTC by R4002 »

Offline R4002

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Re: Loop melody in 27Mhz
« Reply #1 on: August 21, 2019, 1954 UTC »
I know the ROS data mode is used on CB channels 24 and 25 - 27.235 MHz / 27235 kHz and 27.245 MHz / 27245 kHz as well as 27.635 MHz / 27635 kHz...and it has a very melodic sound. 

Youre listening to channel 18 - 27.175 MHz / 27175 kHz so Im not 100% sure.  The ROS mode is popular on 11 meters / the 27 MHz band in Europe...where are you located?
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Offline Josh

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #2 on: August 21, 2019, 2113 UTC »
Never heard ROS sound like that.
Conveniently located near Vincennes Indiana.

Offline Brian

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #3 on: August 22, 2019, 1117 UTC »
Sounds a bit like the interval signals that stations used to broadcast before full programs started in the morning.

Offline R4002

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #4 on: August 22, 2019, 1316 UTC »
Never heard ROS sound like that.

Right.  Maybe somebody playing music on 27.175 for fun?  Or as part of an "interval signal" of sorts to indicate that the channel is about to be used? 

I remember seeing a video on YouTube made by a European CBer - he was hearing Arabic music and melodies on several frequencies on the "low channels" on 26 MHz, I believe 26.785 MHz, 26.795 MHz, 26.865 MHz or nearby frequencies, all in FM mode.  He wasn't sure where they were coming from either.  After the music there would be an OM speaking Arabic.  Good signals too. 
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Offline Leonard

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #5 on: August 22, 2019, 1357 UTC »
I recognize the melody as "its Johnny's birthday" was sung by george harrison. Glad you got a recording.

Offline Lory

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #6 on: August 22, 2019, 1429 UTC »
The music has been going on for hours. Probably all night.
I had heard radio signals like that before, many year ago.

The signal is DX, by propagation

Offline R4002

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #7 on: August 22, 2019, 1651 UTC »
I recognize the melody as "its Johnny's birthday" was sung by george harrison. Glad you got a recording.

The music has been going on for hours. Probably all night.
I had heard radio signals like that before, many year ago.

The signal is DX, by propagation

Looks like you've found yourself an 11 meter broadcaster, of sorts.  Music played on the 11m band / CB band on a regular basis. 

Have you heard the same signals on other frequencies or have they always been on 27.175 MHz / 27175 kHz and in AM mode? 
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Offline Josh

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #8 on: August 22, 2019, 1730 UTC »
Ros mode in comparison;
https://www.sigidwiki.com/wiki/ROS
itd be hard to dance to
Conveniently located near Vincennes Indiana.

Offline Lory

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #9 on: August 22, 2019, 1819 UTC »
Looks like you've found yourself an 11 meter broadcaster, of sorts.  Music played on the 11m band / CB band on a regular basis. 

Have you heard the same signals on other frequencies or have they always been on 27.175 MHz / 27175 kHz and in AM mode?

Don't remember the frequency, but in summer propagation

Offline R4002

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Re: Loop melody in 27Mhz - 27.175 MHz / 27175 kHz CB Channel 18
« Reply #10 on: August 23, 2019, 1543 UTC »
Ros mode in comparison;
https://www.sigidwiki.com/wiki/ROS
itd be hard to dance to

Lol yes indeed it would.  I've heard it on several European-based KiwiSDRs during 11m openings and sporadic-E propagation conditions.  It seems to be centered on 27.235 MHz, 27.245 MHz and 27.635 MHz. 

I know that Germany, Hungary and the Czech Republic allow use of digital modes (ROS, PSK31, etc) on 4 of their legal allocated CB channels (they have 80 channels allocated for use).  Those frequencies are 26.675 MHz, 26.685 MHz, 26.915 MHz and 26.925 MHz.  I've only done cursory monitoring of 11m activity on KiwiSDRs...and while I've heard a lot of paging and other data on various 11m frequencies, I don't think I've heard ROS on those four channels. 
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