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Author Topic: 6790 kHz USB Spanish Language - Rural Radio Telephone Service 1 Oct 2017  (Read 1362 times)

Offline R4002

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***EDIT***

Originally titled "6790 kHz USB Spanish Language - Possible Phone Patch 2213 UTC 1 Oct 2017" I have modified the title of this thread due to the new information provided by FFM and the extensive research they have conducted. 

6790 kHz USB 6.790 MHz USB 6.79 MHz
Spanish language SS speak SS OM/YL Spanish language Spanish voices

Radiotelephone, phone patch, village radio, OM and YL - likely husband and wife having a QSO...

Tuned in at 2213 UTC, was still going at 2218 UTC.  Poor copy.

Possible telephone patch or phone patch-like or radiotelephone link.  Hearing what sounds like a husband and wife talking on 6790 kHz USB.  Possibly a full duplex QSO and I'm hearing the "base station" side of the conversation as at several points the OM and YL are talking over each other.  Casual conversation but this is not two different stations using simplex.  It's one signal with two voice channels being transmitted at once on the same frequency...I have logged several of these oddities in the 67xx and 68xx kHz ranges (6700-6900 kHz roughly) before.  Always in Spanish and always have the same characteristics....usually an OM talking to a YL and possibly children, one transmitter...consistent signal strength.

Naturally, this signal is quite weak.  SIO 111 or so.  I can confirm that its Spanish and that its a OM and YL talking and its the same transmitter...but that's it. 
« Last Edit: October 07, 2017, 0750 UTC by R4002 »
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Offline FFM

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I've noticed the same phenomenon when I hear this phonepatch transmission, I always hear them on the same frequency at the same time, is very rare because duplex systems work in two different frequencies like normal cellphones. However... generally this transmissions comes from isolated argentineana cattle ranches, the distances between farms are so large that the name "villageradio" is not applicable due to the geographical extension that separates these farms. They call it "terrestrial rural radiotelephone service (RRTS)".
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Offline R4002

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FFM,

So these are likely South American in origin?  Which other frequencies have you monitored these transmissions on? 

Thank you for the information about this service.  What's the official title of it in Spanish? Something like Radio Rural Telefono Servicio?   Servicio Radio Telefono Rural?   Most of the time I've heard these in the 6700-6800 kHz area.  If these are remote Argentine cattle ranches, are they operating a crude telephone patch system? 

I'm fascinated by these types of services.  What else do you know about them?  Your information is much appreciated.
« Last Edit: October 04, 2017, 1504 UTC by R4002 »
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Offline FFM

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R4002,

Excuse my delay but it seems that the web site was updated.
Quote
So these are likely South American in origin?
Yes, these service is very used by these argentinean cattle ranches and it was also used by the chilean army for link antartic military bases and the families of the soldiers in the continental chilean territory.
Quote
Which other frequencies have you monitored these transmissions on?
Check the follow frequencies commonly used by these services (in Argentina) (IN USB MODE):
   
    BAHIA BLANCA: 2018, 4868, 7489.5, 10125 KHz.
    BARILOCHE: 3167, 4478, 6845 KHz.
    CATAMARCA: 2396, 4786, 7473 KHz.
    COMODORO RIVADAVIA: 2322.5, 3804.7, 4563.5, 9077 KHz.
    CORRIENTES: 2531.5, 3757, 3952.5, 5095, 7847, 1O330 KHz.
    MENDOZA: 2039, 3841.5, 5851, 7711, 10345 KHz.
    GRAL. PACHECO: 3808, 4920.5, 10107, 13567 KHz.
    RIO GALLEGOS: 2575, 3893, 4458.5, 7542 KHz.

2237,0 KHz
2039,0 KHz
3841,5 KHz
5851,0 KHz
7711,0 KHz
10345,0 KHz    
4028,0 KHz
5352.0 KHz
7480,2 KHz
10193,5 KHz

Quote
What's the official title of it in Spanish?
SERVICIO RADIOTELEFONICO TERRESTRE RURAL. 
Quote
If these are remote Argentine cattle ranches, are they operating a crude telephone patch system?
According what I know this service is also used in Mexico but in Argentina are private companies who administrate this network, as I was telling you before (in the other answer to this post) is possibe to hear the conversation in a unique channel and not in two different as duplex communications do, so I really don't know what is the equipment used by the "telephonic service".

The proced for solicite a link between farms or communicate with a  cellphone of the "normal/common" network is calling to the radiotelephonic central on the "call channel", the central answer to your call and then the client solicite the type of service (talk with other farms or talk directly to a common cellphone), then the central OP ask you the cell number that you want to call or the callsign of the farm that you need to link, you wait while the company link you to the other farm/cellphone, after that you are allowed to talk with the other person.

I'm not beeing very exact but in the follow link you'll find a lot of information (in spanish): http://arieldx.tripod.com/manualdx/variantes/utilitarios/telrural.htm

If you have problems for understand what the google translation says just send me a message with your questions.
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Offline R4002

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FFM,

Thank you very much for this wealth of information.  I look a look at the link provided.  I speak intermediate level Spanish but am a native English (American English) speaker. 

I notice the listing of 6845 kHz for Bariloche, this frequency is also used in the USA for American federal government communications in emergencies (civil defense, disaster response, emergency management, etc).  Seems like each area has 2 MHz or 3 MHz frequencies, 4 MHz frequencies, 6/7 MHz frequencies, and then 9 MHz and/or 10 MHz band frequencies.  Makes perfect sense to me given variations in propagation, time of day, season of year, etc. in order for a high quality voice link to be established. 

In addition to the local/area assigned frequencies, the Radiotelefonia Rural service aka Servicio Radiotelefonico Terrestre Rural (in English that's something like Rural Radiotelephone Terrestrial Service (RRTS) or Rural Radiotelephone Service paired frequency list:

2039 kHz (transmit) paired with 2237 kHz (receive)
3841.5 kHz (transmit) paired with 4028 kHz (receive)
5851 kHz (transmit) paired with 5352 kHz (receive)
7711 kHz (transmit) paired with 7480.2 kHz (receive)
10345 kHz (transmit) paired with 10193.5 kHz (receive)

The existence of a similar service in Mexico explains the Mexican accents I have logged on several frequencies including 6771.5 kHz USB, 6772.5 kHz USB, and maybe 6-10 other frequencies logged in the past several months, nearly all of them in the 6-7 MHz region.  Now knowing that use of various bands is commonplace in Argentina...I presume it is also commonplace in Mexico and other areas where similar services are in use. 

I thank you for providing this information and the link, FFM.  I hope you can continue to contribute your unique skills, language knowledge and receive location to find out more information about the so-called "peskies" (unexplained Spanish language and Portuguese language transmissions heard in the 6700-7000 kHz range, often interfering with pirate radio broadcasts).  It is presumed that most of the Spanish language transmissions, especially those centering around 6900 kHz (and using 5 kHz channel steps, for example, 6900 kHz, 6905 kHz, 6910 kHz, etc) are land-based stations operating outside the amateur radio bands.  The Portuguese language stations are possibly related to fishing fleets in the Atlantic Ocean and use odd frequency steps, with their most popular frequencies being 6925 kHz LSB, 6933 kHz LSB, 6919 kHz LSB, 6868 kHz LSB, 6858 kHz LSB, 6888.8 kHz USB and LSB, and dozens of others. 

Are you able to hear activity on any of those frequencies?  I look forward to any other information you can provide.  :)  Thank you!
« Last Edit: October 07, 2017, 0756 UTC by R4002 »
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Offline FFM

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R4002,

It's a pleasure for me to share all the information that I have about fequencies and all relationated with shortwave bands, I must thank you too for share your listenings and knowledge.
Quote
Are you able to hear activity on any of those frequencies?
For the moment I do not have SSB receiver because the one that I had is borrowed ... however the Portuguese transmissions in LSB comes from ships or from the super big pirate movement that exist in the souther cone, generally the most used frequency by chileans is 6993-6996kcs, argentineans between 6970 and 6990kcs and brazilians use basically everything from 6800 to 7000kcs.

On 6995 is also a "non official simplex comms network" used by OWs from the Salta province in Argentina, some of these transmission comes from other provincies in the north of Argentina. Other very interesting frequency is 6955 LSB that is operated by isolated health rural centres in the Salta province in Argentina, sometimes you hear things like: ...man with half of his body paralized, the local priest is carrying him to the hospital in the city... https://www.youtube.com/watch?v=dUkA81W915A .

I got a new RTL SDR on ebay so in few more time I'll be checking these frequencies again  ;D

Thank you for give me the channels that are used by these probably brazilians fisherers, I'll listen to that frequencies and try to translate what they say for have an idea about what are they talk about.

73!
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Offline R4002

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FFM,

Your posts continue to be a wealth of information!  Glad to hear that you've recently purchased a SDR that can receive SSB transmissions.  The Portuguese speaking stations in the 6800-7000 kHz area are the ones that the pirate radio community wonders about the most.  The general opinion is that they are marine based transmissions and are related to fishing fleets.  I have monitored 6995 kHz before (both USB and LSB) but always in Spanish.  The stations seemed to be based in Venezuela (or at least one of them was).  6999 kHz LSB has also been logged.  While the Brazilians (well, presumed Brazilians) are usually known for using LSB mode, they have been logged in USB as well.  The Spanish speaking stations seem to use USB and LSB equally. 

6955 kHz LSB has been logged before, but the traffic has always been too weak to make anything out. 

I look forward to hearing what you can make out of the Portuguese language traffic found in the 6800-7000 kHz range, in both USB and LSB mode.  The frequency of most interest is 6925 kHz LSB mode, but many others are also often active, including 6919 kHz LSB, 6915 kHz LSB, 6911 kHz LSB, 6933 kHz LSB, and really any frequency in 1 kHz steps.  The Spanish speaking stations seem to favor 5 kHz steps, starting with 6900 kHz as their primary frequency.  Sometimes they will be active on 6905 kHz instead of 6900 but 6900 seems to be the primary frequency.  I have heard operators on 6900 LSB (they use 6900 kHz USB as well, sometimes at the same time as there is traffic on 6900 kHz LSB) refer to the frequency as the "main frequency" for 43 metros for the Americas.  I think this only applies to hobby stations - also known as "freebanders" or "outbanders", and not actual licensed services like the Rural Telephone Radio Service and medical services on 6955 kHz LSB.
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Offline BoomboxDX

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Interesting info here. Probably no chance of hearing deep into South America on 6800-7000 at this location (NW US) but still very interesting to read about it.

Thanks for posting all the info, especially to FFM.
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