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Messages - R4002

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31
10/11 meters / Re: WWV's 25MHz signal?
« on: March 13, 2024, 1746 UTC »
Daily, or almost. 

Same with the FM carrier on 25.950 MHz.

Location: central Virginia - Richmond, VA.

32
10/11 meters / Re: WEXT Remote-26.6850 1810 01 March 2024
« on: March 13, 2024, 1745 UTC »
As a follow up, I found this - one of the recordings I made while listening to the G8JNJ online receiver (receiver located in the UK)

https://www.youtube.com/watch?v=NZ6-lNettH0

Received on 19 February 2024.  Frequency 26.685 MHz 26685 kHz 26.6850 MHz AM 26.685 AM

33
10/11 meters / Re: 11m Band Activity 05 MAR 2024
« on: March 13, 2024, 1744 UTC »
Nice catch re: UK FM CB Channel 7 - that is, 27.66125 MHz FM. 

It seems like channels 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 29, 30, 31, 32, 38, 39 and 40 are the most popular ones, at least from my personal experience.  I've noticed that channels 1 through 9 (so 27.60125 MHz FM to 27.70125 MHz FM) seem to suffer the most as far as SSB QRM goes.  There are others, including channels 16/17, due to a data link system on 27.760 MHz (center frequency).  10-12 kHz wide, with two wide MFSK signals located roughly 4-5 kHz below and 4-5 kHz above the center frequency.  Plus, 27.765MHz is very popular for out of band operation (mostly in Europe)

Pagers on 27.750 MHz, 27.800 MHz, 27.845 MHz, 27.850 MHz, 27.885 MHz, 27.900 MHz and 27.940 MHz also seem to cause some pretty serious QRM when the band is open.

I know UK FM CB Channel 14 is, or was, the base station to base station calling channel or working channel.  DXing on UK FM CB channels 30, 31, 38, 39 and 40 seems to be somewhat popular too.

That is...

27.73125 MHz FM - 27731 FM - UK FM CB Radio Channel 14
27.74125 MHz FM - 27741 FM - UK FM CB Radio Channel 15
27.75125 MHz FM - 27751 FM - UK FM CB Radio Channel 16
27.76125 MHz FM - 27761 FM - UK FM CB Radio Channel 17
27.77125 MHz FM - 27771 FM - UK FM CB Radio Channel 18 - frequent QRM from 27.775 MHz AM or FM
27.78125 MHz FM - 27781 FM - UK FM CB Radio Channel 19 - often getting slammed by taxis on 27.785 MHz AM
27.79125 MHz FM - 27791 FM - UK FM CB Radio Channel 20
27.80125 MHz FM - 27801 FM - UK FM CB Radio Channel 21 - sporadic QRM from 27.8 MHz POCSAG
27.81125 MHz FM - 27811 FM - UK FM CB Radio Channel 22
27.82125 MHz FM - 27821 FM - UK FM CB Radio Channel 23
27.83125 MHz FM - 27831 FM - UK FM CB Radio Channel 24
27.84125 MHz FM - 27841 FM - UK FM CB Radio Channel 25 - QRM from 27.845 MHz / 27.850 MHz POCSAG
27.88125 MHz FM - 27881 FM - UK FM CB Radio Channel 29 - suffers QRM from pager system on 27.885 MHz
27.89125 MHz FM - 27891 FM - UK FM CB Radio Channel 30 - suffers QRM from pager system on 27885
27.90125 MHz FM - 27901 FM - UK FM CB Radio Channel 31 - QRM from 27.9 MHz paging signals
27.91125 MHz FM - 27911 FM - UK FM CB Radio Channel 32 - 27.915 MHz is very popular with US freebanders
27.94125 MHz FM - 27941 FM - UK FM CB Radio Channel 35 - Severe QRM from 27.940 MHz data and POCSAG paging
27.97125 MHz FM - 27971 FM - UK FM CB Radio Channel 38 - QRM from taxi cabs on 27.965 MHz and 27.975 MHz
27.98125 MHz FM - 27981 FM - UK FM CB Radio Channel 39 - 27.980 MHz USB is a popular free band SSB DX freq
27.99125 MHz FM - 27991 FM - UK FM CB Radio Channel 40

34
Via G8JNJ SDR

35
10/11 meters / Re: WEXT Remote-26.6850 1810 01 March 2024
« on: March 13, 2024, 1053 UTC »
26.685 MHz FM? 26.685 MHz AM?

Either way, that’s not one of the (legal) IFB/STL frequencies:


25.870 MHz FM
25.910 MHz FM
25.950 MHz FM
25.990 MHz FM
26.010 MHz FM
26.030 MHz FM
26.050 MHz FM
26.070 MHz FM
26.090 MHz FM
26.110 MHz FM
26.130 MHz FM
26.150 MHz FM
26.170 MHz FM
26.190 MHz FM
26.210 MHz FM
26.230 MHz FM
26.250 MHz FM
26.270 MHz FM
26.290 MHz FM
26.310 MHz FM
26.330 MHz FM
26.350 MHz FM
26.370 MHz FM
26.390 MHz FM
26.410 MHz FM
26.430 MHz FM
26.450 MHz FM
26.470 MHz FM

The lower portion is shared with the 11 meter shortwave broadcast band SWBC band.  25.800 MHz and 25.900 MHz are both used for legal licensed shortwave broadcast.  Of course, the unlicensed but de facto standard two-way radio land mobile use starts at 25.615 MHz (or 25.610 MHz…maybe just easier to call it 25.600 MHz) and goes up to 30.105 MHz. 


Most of the users stay below 28.000 MHz, but not all.  The other day I heard the studio audio on 26.110 MHz FM mixing with Mexican truck drivers (on 26.105 MHz AM) and American hunters in their trucks (on 26.115 MHz AM). 


You might have been hearing a freeband 11m band CB station simulcasting audio.  Certainly wouldn’t be the first time.

The
26.515 MHz - 26.955 MHz low channels and
27.415 MHz - 27.855 MHz high channels


are where the majority of out of band CB comms take place.  There’s also the following CB band plans (partially overlapping)


26.565 MHz - 26.955 MHz - German 80 channel CB channels 41-80.  Straight 10 kHz spacing.  channels 1-40 are identical to the EU/American standard 26.965 MHz - 27.405 MHz band plan.

Only FM mode is allowed on 26.565 - 26.955.  AM, FM and SSB are allowed on 26.965 - 27.405.  German regulations specify that digital modes and gateways (remote stations) are permitted on the 80 channel allocation.  This band plan is usually “DE” in most multi-norm radios.  In addition to Germany, it is legal in Czech Republic, Hungary and possibly other countries.  It also includes the 26.805 MHz FM freeband FM calling frequency. 

The 26565 to 26955 band plan overlaps with most of the 26515 to 26955 low channels or “band C”. 

UK FM CB radio “27/81” band
27.60125 MHz - 27.99125 MHz

10 kHz spacing, NFM mode only. 


Many ops simply cut off the last two digits so 27.601 MHz to 27.991 MHz. 


27.781 FM or 27.78125 MHz FM is UK FM Channel 19. 

The UK has 80 legsl 27MHz CB channels to work with.  The 40 UK FM channels + the 40 European standard EU channels (which are identical to the American / FCC channels, 26965 - 27405, AM, FM, SSB all legal). 


The UK FM band plan overlaps with a good chunk of 27.415 to 27.855 (and up to 27.995 MHz).  Often I hear SSB chatter mixing with AM voice comms and FM voice comms adjacent to UK FM CB activity.  A good example is UK FM CB channel 19 suffering QRM from taxi cab company radio signals…either from Russia (usually FM mode) and/or the Americas (usually AM mode). 

27.775 MHz AM and/or FM
27.78125 MHz FM
27.785 MHz AM and/or FM

It’s easy to see how messy it can (and does) quickly get.  Add paging systems, 11m SSB comms, and of course folks running SSTV on 27.700 MHz (UK FM CB channel 11 is 27.70125 MHz FM) and it’s QRM city. 

The 26.200 MHz to 26.960 MHz and 27.450 MHz to 28.000 MHz spectrum are both heavily used for paging systems. 

26.200 - FM carrier when idle
26.220
26.250
26.300
26.350
26.400
26.450
26.500
26.550
26.600
26.625
26.630
26.635
26.645
26.650
26.655
26.695 - UK hospital paging
26.700 - UK hospital paging
26.705 - UK hospital paging
26.745 - UK hospital paging
26.750 - UK hospital paging
26.755 - UK hospital paging
26.780
26.785
26.800
26.815
26.835
26.845
26.850
26.855
26.865
26.895
26.900 - UK paging
26.935
26.945 - data link systems, Russia
26.950 - paging, Europe
26.955
26.960 - data link systems, Russia
27.100
27.250
27.300
27.350
27.360
27.450 - FM carrier when idle
27.500
27.505 - 10-20 kHz wide POCSAG
27.510
27.550
27.600
27.620
27.650
27.700
27.750
27.760 - data links, 10-12 kHz wide
27.800
27.845
27.850
27.885 - voice + POCSAG paging
27.900
27.950
29.750
29.800 - often very busy
29.850
29.900 - often very busy


36
Listening via the G8JNJ SDR this morning - 1310 UTC.  29875 FM coming in SIO 444 to SIO 555, nice strong FM signals.  29750 FM 29.75 MHz FM also with some more dramatic fading. 

29.8750 MHz FM [CSQ] going basically nonstop at 1315 UTC.  Sounds like Japanese.   Fishery radio fisheries radio chatter comms 29,875 29.875MHz FM

37
26.7650 MHz AM coming in nicely this afternoon (US East Coast time) 2010 UTC - 2015 UTC

Some additional land mobile comms coming in on:

25.685 MHz AM - Spanish language taxi dispatch lady
25.695 MHz AM - Taxi cab dispatcher, YL dispatch lady Mexico, active frequency / user LMR land mobile
25.815 MHz AM - Spanish language YL dispatcher
26.025 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
26.035 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
26.055 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
26.135 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
26.315 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
26.335 MHz AM - Taxi cab dispatcher, YL dispatch lady Mexico, active frequency / user LMR land mobile
27.515 MHz AM - Taxi cab dispatcher, YL dispatch Spanish language
27.525 MHz AM - US truck drivers / truckers using export radios
27.535 MHz AM - US truck drivers / truckers using export radios
27.575 MHz AM - Taxi cab dispatch - YL dispatcher Spanish language
27.635 MHz AM - US truckers, busy frequency
27.725 MHz AM - Taxi cab dispatcher - YL with end of transmission beeps
27.755 MHz AM - Taxi cab radio dispatch 27755 AM 27.755 MHz AM strong signals
27.815 MHz AM - Taxi cab radio comms, land mobile LMR user - Spanish language
27.905 MHz AM - US freeband CB radio chatter, possibly base stations
27.915 MHz AM - US truck drivers or other business user, heavy fading 27.915MHz 27915kHz

38
Hello all,

This is an interesting one, now that I’ve managed to catch the voice transmissions as well as the paging data. 

The voice messages include a “tone out” (possibly a selective calling tone) burst prior to the voice message.  Frequency is 27.885 MHz. 

The recordings linked below were all made via an online SDR in the UK, specifically the G8JNJ SDRs:

27.885 MHz FM Alert Tones Voice Message + Paging Signals [Part 1] G8JNJ SDR - 27 Feb 2024
https://youtu.be/FlRQfJUgLBI

and

27.885 MHz FM Alert Tones Voice Message + Paging Signals [Part 2] G8JNJ SDR - 27 Feb 2024
https://youtu.be/VUbcwUtgOiA


Voice message for “Part 2” begins at the very beginning of the video. 

For “Part 1” there is an in-progress voice message when I start recording.  At 0:28 in, you can hear the “tone out” burst - one long tone followed by two short tones…followed immediately by a voice message.   


Numerous other videos of the paging signals - including the various bandwidth POCSAG signals on frequency have been captured and are on the regular “R4002” page. 


The links above are the best capture I’ve gotten of the voice messages though. Here are the other two videos of the voice message:

27.885 MHz FM Data Paging + FM Voice Transmission UNID Source [G8JNJ SDR] 23 Feb 2024 [Part 1]
https://youtu.be/bFesHLxAHvc

^ voice transmission in progress at the very beginning of the recording.  This one is the worst quality of the clips I managed to get.  There is a “Part 2” video from 02/23/2024 but it only shows data / paging signals and increasing QRM from freeband CB radio signals on 27.880 MHz USB, 27.885 MHz LSB and 27.885 MHz AM - U.S. out of band 11 meter CB signals starting to fade in.

Older video / audio recordings of the voice paging pager / POCSAG paging on 27885 FM:

27.885 MHz FM POCSAG Paging + FM Voice Pager 27MHz Band 11M Band [G8JNJ SDR in UK] - 15-Dec-2023
https://youtu.be/C6R50M8Q-dY

^ from December 15th, 2023.  Tone out / alert tone at 0:16 in, follows the same format - one long tone burst followed by two short tone bursts followed by a voice message transmission (FM mode) followed by a moment of unmodulated FM carrier…then it switches back to paging data bursts. 

27.885 MHz FM Voice Paging + Data Bursts Pager System POCSAG Paging - Via G8JNJ SDR - 24 Oct 2023
https://youtu.be/g-8CHON_QxU

^ from October 24, 2023.  The voice message is in progress when the recording starts. 


 
 


 




 

39
10/11 meters / UK FM CB Activity 1945 UTC 26 Feb 2024
« on: February 26, 2024, 2027 UTC »
The band is lighting up this afternoon.  Lots of activity on UK FM CB radio channel 19, plus numerous others:

27.601 FM 27.60125 MHz FM - UK FM CB Channel 1 - FM carriers and voice, lots of SSB QRM - possibly music carriers?
27.631 FM 27.63125 MHz FM - UK FM CB Channel 4 - unmodulated FM carrier (???), QRM from 27.635 MHz
27.681 FM 27.70125 MHz FM - UK FM CB Channel 9 - another carrier - tons of QRM
27.731 FM 27.73125 MHz FM - UK FM CB Channel 14
27.751 FM 27.75125 MHz FM - UK FM CB Channel 16
27.781 FM 27.78125 MHz FM - UK FM CB Channel 19
27.791 FM 27.79125 MHz FM - UK FM CB Channel 20
27.831 FM 27.83125 MHz FM - UK FM CB Channel 24 - busy, QRM from AM freeband CB signals on 27.835 MHz
27.841 FM 27.84125 MHz FM - UK FM CB Channel 25 with QRM from 27.845 MHz AM taxi cab dispatch
27.861 FM 27.86125 MHz FM - UK FM CB Channel 27
27.901 FM 27.90125 MHz FM - UK FM CB Channel 31
27.911 FM 27.91125 MHz FM - UK FM CB Channel 32
27.921 FM 27.92125 MHz FM - UK FM CB Channel 33 with QRM from 27.915 MHz AM and 27.925 MHz AM truck drivers
27.931 FM 27.93125 MHz FM - UK FM CB Channel 34
27.951 FM 27.95125 MHz FM - UK FM CB Channel 36
27.961 FM 27.96125 MHz FM - UK FM CB Channel 37
27.971 FM 27.97125 MHz FM - UK FM CB Channel 38 - calling frequency
27.981 FM 27.98125 MHz FM - UK FM CB Channel 39
27.991 FM 27.99125 MHz FM - UK FM CB Channel 40

27.841 FM (UK FM CB Channel 25) is actually as busy as 27.781 FM.  Unfortunately there's enough Latin American taxi cab comms starting to come in that the AM mode land mobile comms QRM is becoming a thing, especially on 27.78125MHz

Plenty of in-band activity and SSB all over the place.  26.805 MHz FM active as well.   

UK paging pager signals POCSAG on 26.745 MHz, 26.705 MHz, 26.695 MHz, 26.350 MHz, 26.250 MHz and 26.200 MHz. 

40
26.765 MHz AM is a good indicator of propagation to Mexico.  Plenty of others, including numerous in the 27.405 MHz - 27.995 MHz range, using AM mode. 

I’m hearing the taxi cab dispatcher YL right now at 1915 UTC via a local handheld receiver.  She’s also coming in on the W3HFU SDR. 


41
10/11 meters / Class C CB (RCRS) 27 MHz Telemetry Yahoo Group Archive
« on: February 26, 2024, 1816 UTC »
Info from the VHFDX email chain, good group of 25-30 MHz and VHF low band DXers (as well as other bands, including 22m interest).  Given the amount of data traffic on 27.255 MHz and the other RCRS frequencies, I wanted to share this with the HFU forums so this link is archived

https://web.archive.org/web/20201214034230/https://groups.yahoo.com/neo/groups/Class_C_Telemetry/info

42
They’ve been coming in basically daily.  Nice to hear actual SWBC on the 11 meter band

43
26.765 MHz AM active yesterday with some nice signals, YL dispatcher.

44
Received via the W3HFU SDR and locally (local receive setup consisting of a PNI Escort HP 82 handheld AM / FM CB walkie talkie with a HYS 51” telescoping whip. 

Recording transmitted at least twice.  Included English translation of German, plus crowd noise.  Waterfall waveform shows no delay in the two signals…but the 26.855 MHz FM signal had more FM deviation. 


26805 FM 26,805 kHz 26805 MHz
26855 FM 26,855 kHz 26855 MHz

Recording of the signals as received via SDR:

[Part 1]
https://youtu.be/-Uxs8OSMEf8

[Part 2]
https://youtu.be/_D0d_wHaJdA

The first SDR clip also shows a strong AM signal on 26.825 MHz, unrelated to the simulcast on 26.805 FM and 26.855 FM. 

And received locally on the handheld CB

[Part 1]
https://youtu.be/r9pW0ORO8OY

[Part 2]
https://youtu.be/3XCGizYum3c


The PNI HP82 is in DE mode 80 channel CB radio mode, so 26.805 MHz FM is channel 65 and 26.855 MHz FM is channel 70. 


The 26.855MHz signal sounds a bit distorted, likely due to the higher level of FM deviation on that signal. 

The band was open to Europe and the UK as well as the Americas - signals from the U.S. and Latin America were booming in all at once, with lots of FM mode CB radio signals mixing in with domestic AM and SSB, including French and German CB radio traffic on channels 38 and 39, often completely blocking LSB signals on 27.385 MHz and 27.395 MHz. 

FM CB radio activity coming in on the known DX calling channels frequencies 27.305 MHz and 27.315 MHz / CB Channel 30 FM and 31 FM.  American FM CB activity on 27.275 MHz FM (CB Channel 27 FM) and 27.295 MHz FM (CB Channel 29 FM) plus 30 and 31, with lots of severe QRM at points.  Channels 35-40 had AM, FM and SSB going all at once. 

Lots of German language signals on 26MHz band German FM CB channels and the UK FM channels were busy too.  27.78125 MHz FM was very busy, as to be expected.  Lots of Latin American language taxi dispatch chatter, including the 27.785 MHz AM Mexican taxi cab dispatch LMR comms, plus American free band CB signals, lots of SSB but also AM, including 27.845 MHz AM, 27.855 MHz AM, 27.865 MHz AM, 27.905 MHz AM, 27.915 MHz AM, 27.925 MHz - possible militia comms on 27.925MHz AM with QRM from 27.92125 MHz FM and 27.93125 MHz FM

45
Hearing locally on my Tecsun portable and via several online receivers on the East Coast of the USA. 

Strong signal on the W3HFU receivers.  Solid SIO 555.  Signal strength a solid S7...peaking up to S8 and S9 at points.  Strong AM modulation, almost exactly 10 kHz wide on 25900 kHz 25.9 MHz

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