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Messages - R4002

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421
1030 UTC / 1430 local


Even more ISM hooks all over the 26-28 MHz region on the waterfall today.  A couple of them are actually within the 26957-27283 ISM region. The 26.945 MHz and 26.960 MHz paging systems are, as to be expected, super busy.  26945 especially so.  The 27200 FM guys were really strong.  27135 AM (channel 15 AM) is apparently used like 27185 AM is here in the USA.

26945 kHz FM - 26.945 MHz FM - FSK data bursts - likely paging systems (numerous signals on frequency)
26960 kHz FM - 26.960 MHz FM - FSK data bursts - likely paging systems (numerous signals on frequency)
27125 kHz FM - 27.125 MHz FM - Weak FM signal, including several seconds of unmodulated carrier
27130 kHz FM - 27.130 MHz FM - Sounds like taxi cab dispatch
27135 kHz AM - 27.135 MHz AM - Two OM CBers chatting, fair signals - busy nearly constantly
27195 kHz FM - 27.195 MHz FM - Weak FM signals on frequency, some QRM from the 27.200 MHz guys
27200 kHz FM - 27.200 MHz FM - Two OM CBers chatting, very strong signals, SIO 555 nice FM audio
27255 kHz FM - 27.255 MHz FM - Caught tail end of a FM voice transmission in Russia
27585 kHz FM - 27.585 MHz FM - Weak YL voice heard, presumed taxi dispatcher/ taxi controller 27.585 FM

422
LO66ou grid, Izhevsk Russia

Band pretty quiet this evening (2300 local time likely explains why) - but the 26.945 MHz and 26.960 MHz paging systems were very busy.  26.960 MHz had signals on it nearly nonstop.  Lots of "hooks" (ISM signals) both within and above and below the 26957 - 27283 ISM band. 

26945 kHz FM - 26.945 MHz FM - FSK data bursts - likely paging systems (numerous signals on frequency)
26960 kHz FM - 26.960 MHz FM - FSK data bursts - likely paging systems (numerous signals on frequency)
27130 kHz FM - 27.130 MHz FM - YL taxi dispatcher (I think) - taxi cab controller
27135 KHz FM - 27.135 MHz FM - CBer, Russian (obviously) - much stronger than the 27130 signal
27225 kHz AM - 27.225 MHz AM - OM CB operator heard, weak signal
27645 kHz FM - 27.645 MHz FM - Taxi cab dispatch, YL dispatcher (weak)




423
10/11 meters / Re: 11 meter beacons
« on: September 08, 2021, 1601 UTC »
I had very good reception of the 69BY beacon yesterday.

On which frequency? 27550 or 27610?

27609.9 IIRC.

Okay cool - it's good to get a confirmation that the 69BY 11 meter beacon is still on the air and using 27610 / 27.610 MHz...well, 27609.9 / 27.6099 MHz anyway

424
Hearing two Spanish-speaking OMs on 27.065 MHz AM - 27065 AM - CB channel 9.  Strangely, 26585 AM, 26705 AM, 26715 AM are all quiet...but 27065 AM is busy.

The rest of the band is basically dead at the moment..

425
Yep, 27.015 AM is one of them (CB channel 5). 

Others to check when 27015 AM is active are:

26585 AM / 26.585 MHz AM and nearby channels (26.565 MHz, 26.575 MHz, 26.595 MHz, etc.)

26705 AM / 26.705 MHz AM
26715 AM / 26.715 MHz AM

and

27065 AM / 27.065 MHz AM - that's right, CB channel 9.  26705 AM and 26715 AM are very popular with stations in Florida, Puerto Rico and other parts of the Caribbean.  26585 AM is one of the popular Mexican trucker channels. 

426
10/11 meters / Re: 11 meter beacons
« on: September 06, 2021, 1526 UTC »
I had very good reception of the 69BY beacon yesterday.

On which frequency? 27550 or 27610?

427
Morning activity - not sure if the band is starting to wake up or if this is just sporadic-E

25695 AM - YL taxi cab dispatcher with roger BLEEP
25745 AM - Spanish language, presumed taxi cab dispatch
26175 AM - OM and YL chatting, Spanish language, possibly also a taxi dispatcher (weak)
26205 AM - YL taxi dispatcher - Spanish language
26365 AM - Spanish language, weak, OMs chatting...possibly truckers, does not sound like taxi cab dispatch lady
26455 AM - Spanish language chatter with roger beeps, possibly a taxi dispatcher
26515 AM - Spanish language, very weak
26565 AM - Spanish speaking OM heard
26585 AM - Spanish language, multiple stations at points, Mexican trucker and taxi common channel
26665 AM - Spanish language, weak
26705 AM - Spanish language, heard mention of Puerto Rico (the usual suspects here - expect 26715 AM and others)
26935 AM - UNID, AM voice activity, weak
27015 AM - Spanish language - CB channel 5

428
10/11 meters / Re: 11 meter beacons? Remember 27.145USB?
« on: September 06, 2021, 1355 UTC »
Huh... Does anyone remember what that purring, pulsing-like, beacon was around 1990-1991 on 27.145MHz, heard best in USB? (a.k.a. between CB CH's 15 and 16.) That was with a President HR2510, at the time, and a Firestix 4ft indoor GND-plane. I assume it to be ISM now.

I believe there is, or was, a beacon based in Thailand on 27500 (or close to 27500) - there are, or were, several beacons listed on or around the 27.500 MHz region

429
10/11 meters / Re: 11 meter beacons
« on: August 14, 2021, 2257 UTC »
There have been some heard on and around 27.500 MHz / 27500 kHz.  I know there was or is a QRP beacon on 27.125 MHz / 27125 kHz - CB channel 14 - ID "AOH" doing 36mW output power if I remember correctly, 

The area around 27.140 MHz - 27.145 MHz is home to the 14RS000 beacon and I know there is or was a beacon out of Russia on 27.140 or 27.141 or thereabouts.

There's also the 26510 kHz / 26.510 MHz beacon out of Germany and the 27.205 MHz FM channel 20 repeater in Sweden I believe. 

There's a list on the HFU Wiki too :)

430
The 161.670 MHz to 161.790 STL/remote broadcast pickup band regulations permit use of offset frequencies, 15 kHz or 7.5 kHz offsets...putting that band in-line with the standard 7.5 kHz VHF high band band plan:

161.6700 MHz
161.6775 MHz - offset
161.6850 MHz - offset
161.6925 MHz - offset
161.7000 MHz
161.7075 MHz - offset
...
up to
161.7825 MHz - offset
161.7900 MHz

The railroad band is another interesting segment - 160.2000 MHz to 161.5650 MHz...15 kHz / 7.5 kHz channel steps.  Most railroads are still using the 15 kHz channel steps but the railroads are updating their licenses for NXDN (aka NEXEDGE) narrowband digital voice (4K00F1E emission).  I live in a city that operates as a major railroad junction for CSX, Norfolk Southern and Amtrak and I'm yet to hear any digital voice on the railroad frequencies.  All the activity is also still on the 15 kHz channels. 

The railroad systems are interesting compared to other land mobile systems in that they're relatively low powered (usually the base stations are licensed for 20-50 watts output power) and there's very little use of CTCSS.  There's a massive CSX classification yard about 1 mile straightline distance from my QTH and yard control radio is very active - same with the Maintenance of Way channels (which are usually also within the 160.200 to 161.5650 AAR railroad band) The yard also uses a voice/data paging system on 462.925 MHz...also licensed for 25 watts.   The most active frequencies are the road and yard control frequencies, which can be monitored on a handheld radio easily.

 


Also check out the HOTD/EOTD (Head-Of-Train-Device and End-Of-Train-Device) UHF telemetry frequencies are other ones to look at:

452.9375 MHz
457.9375 MHz

There are other telemetry/datalink frequencies used by railroads, including others in the 452.9250 MHz - 452.9750 MHz range, the 44.5800 MHz BNSF telemetry network and others. 

A few weeks ago I monitored a drone operating crew that was using a drone to survey/inspect a railroad right-of-way...they were using 151.8050 MHz (which is one of the regular old VHF high band business/industrial radio service frequencies).  One of them sounded like they were in a chase vehicle while the other was in a fixed position.  The itinerant frequencies are also sometimes used (VHF high band itinerants are 151.5050 MHz, 151.5125 MHz, 151.6250 MHz, 151.7000 MHz, 151.7600 MHz, 154.5275 MHz, 158.4000 MHz and 158.4075 MHz). 

431
Almost every time there's a band opening and there's activity on the lower channels (almost always AM voice traffic), there's also AM voice on the A channels 26.995 27.045 27.095 27.145 27.195.   27.145 MHz and 27.195 MHz seem to be the most popular...but I have heard folks chatting on 26.995 MHz and 27.045 MHz as well.  27.095 suffers from QRM from channel 11 27.085 MHz (just like 27.195 suffers from QRM from channel 19). 

It makes sense too - hiding on one of the five A channels vs. using an out of band channel is probably better as far as antenna performance goes (presuming the CB antenna you're using is tuned for the center of the band, which, of course, is 27.185 MHz ;)).   That being said, the low channels - 26.515 MHz - 26.955 MHz - are often just as busy when the band is rolling as they say.  The frequencies above 26.6 MHz or 26.7 MHz seem to be the most popular, see the channels that are "down one band" from the popular AM DX frequencies (the obvious exception being 26.905 MHz and 26.915 MHz, both of which are very popular when the band is open).  26.955 MHz seems to be used by truckers and hobbyists alike.

27.255 MHz has had some data on it during recent band openings...although nothing strong enough to overwhelm the voice traffic on frequency.  26.995 and 27.255 are the two frequencies most commonly used by the serious (4-watt or 10-watt) data link and telemetry systems so those are the ones I'd focus on as far as finding hidden data networks within the CB band.

432
https://www.youtube.com/watch?v=cFIMeV-LSJ8

Heard several stations chatting on 26815 AM 26.815 MHz AM before I started the video recording.  I actually was able to speak to two of the stations (after I stopped recording) using the CRE 8900 radio in the video...and the antenna I used was less than ideal for sure.  Transmitter power output is around 8-10 watts AM carrier power, good band conditions recently on 11 meters. 

434

https://www.youtube.com/watch?v=yYsu4cjCDe0

Recorded during a big band opening on 11 meters back on 06/14/20. 

435
What sort of signal?  FSK?

I noticed tones and music (as well as regular AM voice traffic) during one of the many recent band openings on 27145 kHz / 27.145 MHz as well as 27195 kHz / 27.195 MHz.

https://www.youtube.com/watch?v=oucMzYLCR1E

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