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Messages - R4002

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46
27.725 MHz FM via the W3HFU KiwiSDR at 1800 UTC tune in.  Some pretty serious fades....but it sounds like the typical fishery radio chatter.  Asian fishing fleets Chinese fishing radio dedicated fishery radiotelephone

27.5 MHz - 39.475 MHz 25 kHz spacing - normal mode for 480 channels, FM voice, 25w output - 16K0F3E
27.5 MHz - 39.4875 MHz 12.5 kHz spacing - export mode 960 channels NFM voice, 25w output - 11K0F3E

47
27,755kHz AM 27.755 MHz AM, SIO 222 with some very dramatic fading.  Spanish language, Mexican accented YL reading alphanumeric taxi cab IDs, addresses, phone numbers...taxi cab dispatcher on 27 MHz band.  27.755 MHz, AM mode.   

First noted at 1750 UTC


48
Starting hearing the dispatch lady - I believe out of Central Mexico or Northern Mexico on 26765 kHz 26.765 MHz 26.7650 MHz AM around 1630 UTC today.

At 1700 UTC or so, signal levels still roughly the same.  Coming in nicely on some U.S. East Coast online SDR receivers at 1730 UTC and now - 1740 UTC. 

Tell-tale end of transmission tone burst (EOT) - aka the "Roger beep" basically an automatic identification system. 

Frequency 26.7650 MHz AM is CB Channel 21 down one band.  Band C, Channel 21 on the regular 25.615 MHz - 28.305 MHz 240 channel export radio band plan....or Channel B21E / B21E AM on the alphanumeric channel plan.

Some QRM from FM mode traffic around 1741 UTC / 1742 UTC...26.765 MHz FM coming in at the same time as 26.765 MHz AM. 

Also noting some European based paging signals on 26.695 MHz, 26.745 MHz...so there's still somewhat of an opening to Europe / the UK, which is likely where the FM CB signals on 26765 are coming from. 

49
April 15, 2024.

Location:  local receive in Richmond, VA
Plus several other U.S. East Coast online SDR receivers, including N1NTE and W3HFU

Time: 1730 UTC

27.195MHz RCRS frequency 27,195 27195kHz 27.1950 MHz AM mode.  Spanish language YL dispatcher with various data signals down closer to the noise floor. 


50
Listening via the G8JNJ SDR at 1750 UTC tune-in time.  Numerous transmitters active on 31.325 MHz, various signal strengths.  Tell-tale polytone data signal

In addition to 31325 kHz / 31.3250 MHz, EPAR data bursts are coming in on:

31.4375 MHz
31.6375 MHz
31.6875 MHz
31.9250 MHz
31.9750 MHz

However 31.325 FM is the most active frequency, at least at the moment.  It's been a while since I've heard the EPAR system.  Sort of a de facto beacon.


51
Via the G8JNJ SDR receiver located in the SW UK.  28975 kHz FM NFM 28,975 28.975.0 MHz.

I managed to get a video clip of the activity on 28.975 MHz

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

Noted these guys on numerous additional frequencies, including:

27.500 MHz FM
27.525 MHz FM
27.575 MHz FM
27.600 MHz FM with heavy QRM from SSB CB signals and UK FM CB ch. 1 - freq 27.60125 MHz FM
27.750 MHz FM
27.775 MHz FM
27.875 MHz FM with QRM from Russian taxi cab dispatcher YL land mobile comms on 27875 FM
27.925 MHz FM
27.975 MHz FM
28.025 MHz FM
28.175 MHz FM
28.225 MHz FM
28.350 MHz FM
28.375 MHz FM
28.725 MHz FM
28.775 MHz FM
28.825 MHz FM
28.875 MHz FM
29.000 MHz FM
29.150 MHz FM
29.625 MHz FM - QRM from legit ham signals
29.700 MHz FM
29.750 MHz FM
29.775 MHz FM
29.825 MHz FM
29.875 MHz FM
29.925 MHz FM
29.950 MHz FM
30.075 MHz FM
30.125 MHz FM
30.150 MHz FM
30.175 MHz FM

and many more above 30 MHz

52
10/11 meters / Fisheries Comms 27.5875 MHz NFM Asian Fishermen
« on: March 29, 2024, 1325 UTC »
This is a new one for me.  They're using 12.5 kHz offsets...but I've never logged the 12.5 kHz offset channels below 29 MHz. 

27.5875 MHz NFM 27587.5 kHz NFM [CSQ] sounds like Japanese language. SIO 444 at 1320 UTC on the G8JNJ SDR

53
Started listening at 1230 UTC 29-March-2024 24-03-2024 via the G8JNJ SDR.  This is just 10 minutes of listening.  They are all over the 10 meter band...and all over the 30 MHz band, 31 MHz band...and up into 32 MHz / 33 MHz. 

Asian fishermen on the 27.5 MHz - 39.5 MHz FM Dedicated Fishery Radiotelephone system.  12.5 kHz / 25 kHz spacing.

27.650 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27650 FM, QRM from CB radio, pagers
27.750 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27.75 MHz, very severe QRM from CB radio
27.775 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27775 FM
27.800 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27800 FM
27.850 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27850 FM
27.875 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27875 FM
27.900 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27900 FM QRM from CB radio, paging signals, FSK
27.925 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27925 FM QRM from CB radio, Russian taxi cab radio chatter
27.950 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 27950 FM QRM from CB radio
28.000 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28000 FM
28.025 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28025 FM QRM from CB radio
28.200 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28200 FM with QRM from Russian taxis on 28.195 MHz FM
28.225 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28225 FM with QRM from Russian taxis on 28.215 MHz FM
28.350 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28350 FM
28.425 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28425 FM
28.550 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28550 FM QRM from 28.555 MHz AM (!!!!)
28.625 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28625 FM
28.700 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28700 FM
28.775 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28775 FM
28.800 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28000 FM
28.825 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28025 FM
28.875 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28875 FM with QRM from Russian taxis on 28.885MHz FM
28.925 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28925 FM
28.975 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 28975 FM
29.000 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29000 FM
29.025 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29025 FM
29.050 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29050 FM
29.075 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29075 FM
29.100 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29100 FM
29.125 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29125 FM
29.150 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29150 FM
29.175 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29175 FM
29.200 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29200 FM
29.225 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29225 FM
29.250 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29250 FM
29.300 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29300 FM
29.325 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29325 FM
29.425 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29425 FM
29.475 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29475 FM
29.500 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29500 FM
29.575 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29575 FM
29.600 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29600 FM 29.6 MHz FM
29.625 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29625 FM
29.650 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29650 FM heavy QRM
29.700 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29700 FM
29.725 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29725 FM
29.750 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29750 FM
29.800 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29800 FM heavy QRM from POCSAG pager on 29.8 MHz
29.825 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29825 FM
29.875 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29875 FM
29.975 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 29975 FM
30.000 MHz FM [CSQ] - Fishermen chatting, fishing fleet comms fishery radio chatter 30000 kHz FM QRM from FM carriers on 30.000.0 MHz

and tons and tons of signals above 30 MHz.  30.025 MHz, 30.100 MHz, 30.175 MHz, 30.200 MHz, 30.225 MHz, 30.300 MHz, 30.475 MHz, 30.500 MHz, and so on. 


54
27.015 MHz (Channel 5) is almost as bad as Channel 6.

Also see: 

26.585 MHz AM
26.595 MHz AM
26.705 MHz AM
26.715 MHz AM
27.065 MHz AM (Channel 9)

26.585 MHz AM is a very popular Mexican trucker frequency.  The nearby channels, especially 26.565 MHz AM, 26.575 MHz AM, 26.595 MHz AM are also very popular, especially when the band is open.  Other honorable mentions include 26.475 MHz AM, 26.405 MHz AM, 26.375 MHz AM, 26.105 MHz AM..but 26.585MHz is a good place to start. 

CB Channel 9 as well as 26.705 MHz AM and 26.715 MHz AM are very popular calling frequencies for Spanish speaking stations.  Puerto Rico is often heard on 26.705 and 26.715.  They'll pop up on 26.695 MHz AM, 26.725 MHz AM and other nearby frequencies too. 

and, as far as SSB goes:

26.555 MHz LSB - Latin American SSB calling - see also: 26.540 MHz LSB, 26.545 MHz LSB, 26.570 MHz LSB
27.455 MHz USB - Latin American SSB calling
27.515 MHz LSB - Caribbean calling frequency
26.225 MHz USB - Latin American SSB calling - see also: 26.235 MHz USB, 26.240 MHz USB, etc.

26.285 MHz USB is designated as an alternate calling frequency, but it is rarely used for that purpose, at least in the Americas.  I've heard more AM mode chatter on 26.285 MHz (out of the Americas - including truckers - since 26.285MHz is Channel 19 down two bands) and FM mode chatter (out of Europe and Asia) then I've heard SSB DXers.   I'm listening to 26.285 MHz right now (1226 UTC on March 29th, 2024) on the G8JNJ online SDR and there is a very loud and very clear Russian land mobile system on the frequency in NFM mode.  26.285 MHz FM.  Taxi cab radio system, radio taxi dispatcher / taxi controller, YL dispatcher "Olga" RU taxi cab dispatch on 26285 FM.

55
Sadly a lot of radios have suffered the same fate ("big-truck-itis").  Lots of vibration over the years just wrecks the solder joints.  Sadly that issue is well enough known to operators and techs alike that some CB operators I've known have cautioned against using certain radios for heavy duty service because of the poorer quality of the solder and a resulting tendency to fail quickly due to the constant vibration.

The radio in question was a Voyage VR9000, which is better known as the Galaxy DX 88HML or Superstar 3900F.  It's a Superstar 3900 with a built-in frequency counter. 

I never had that issue with that particular radio, I used it mobile for many years (in a sedan though) and used it as a base station.  I sold it when I liquidated my collection of CB/11m equipment several years ago (along with several nice examples of older generation Superstar 3900 radios) and now I really hate myself for having done that.  I wish I had held onto my Superstar 3900 or my Superstar GR (which was a rebranded President Grant Export with low/mid/high bands, 26.515 MHz - 27.855 MHz, AM/FM/SSB and a 6-digit frequency counter).

56
26.765MHz AM 26765 kHz AM 26,765 AM taxi dispatch, YL dispatcher - Spanish language.

Started coming in somewhat early today, around 1300 UTC or so.  Good signals at 1430 UTC and now at 1820 UTC locally and on various U.S. East Coast SDR receivers.  Also was able to copy the dispatcher (but not the drivers) on SDR receivers located in the UK.  Fair to good signals. 

57
Yep, most drivers stay below 28 MHz. 

Those Galaxy rigs are nice.  I’ve had both the DX 949 and later a DX 959.  The 959 had a nice 120 channel “channel kit” installed, making it a 3-band radio low channels/mid channels (legal CB band) and high channels.  26.515 - 27.855 MHz.  It also had an opened clarifier +10 kHz/-5 kHz transmit and receive, some parts of the receiver updated…and so on.  No, the modulation limiter was not removed. 

I ran it with an Astatic M6B-D104 power mic and an Astatic 636L mic. 

The 949 and 959 are the same radio, the only difference is the 959 has a built in frequency counter.  I know the Galaxy rigs aren’t the best SSB rigs, but they absolutely scream on AM.  With the power mic, I would run the radio’s mic gain setting at 50% or so and the modulation peaks would still be slightly over 100%.  With the 636L, I would set it at 75% or so and it would give me that nice loud punchy audio without distortion. 

Real classic AM “trucker radios” - like the Cobra 25, Cobra 29 and Uniden PC66/PC68/PC76/PC78.  The Galaxy radios have lots of audio and really punchy if you set them up right with a quality microphone.  Same with the classic Cobra and Uniden rigs. 

CB is very much a useful tool for over the road work.  Just being able to listen to channel 19 is quite useful, especially during adverse conditions. 

In the state I live in, the state DOT roadside assistance trucks all have Uniden CB radios and K40 antennas as part of their standard radio setup.  Many of the other DOT vehicles have CB equipment as well, but the motorist assistance guys see the CB as a requirement to do their job.

Many loading facilities, etc. require that all trucks have CB gear for the dispatcher (“guard shack”) to talk to the trucks directly.  I know that one of the local quarries they have the “DISPATCH OFFICE CB CH 23” sign right at the main gate where dump trucks come in to get loaded.  The dispatch office has a nice 5/8 wave base antenna and a very commanding signal. 


They also have their company radios (VHF high band) for talking to their company trucks.  Ironically enough, all the company trucks have CB gear in them as well as company radios. 


Just like the DOT trucks, the CB gear is used for talking directly to private contractors on site, listening to truckers on 27.185 MHz AM (CB Channel 19) and talking to truckers on the same.

58
Hearing the usual chatty fishermen on 31.000 MHz FM [CSQ] at 1215 local time / 1615 UTC.  31.0 MHz NFM 31000 FM carrier squelch (no squelch tone used). 

Interesting time for these guys to be coming in, usually they're stronger in the morning or evening, vs. middle of the day.  Chances are the other frequencies may start becoming active shortly too.

Fishing trawlers high HF band / VHF lowband FM radiotelephone system, originally out of China:


Original specification:
27.500 MHz to 39.475 MHz - 27.5MHz - 39.5MHz
25 kHz spacing, FM voice 16K0F3E emission
Channelized
480 channels, straight sequence

27.500 MHz FM - Channel 001
27.525 MHz FM - Channel 002
27.550 MHz FM - Channel 003
27.575 MHz FM - Channel 004
and so on (up through 10 meters) up to

39.425 MHz FM - Channel 478
39.450 MHz FM - Channel 479
39.475 MHz FM - Channel 480

Power output 25w.  Dual mode signalling, 300 baud and 1200 audio-frequency shift keying for individual calling, ship to ship call, emergency call, ship to shore station call, group call, fleet broadcast signal and other purposes.  System is entirely carrier squelch operated.

There are modified variants sold out of Taiwan and other places that use 12.5 kHz spacing to increase the number of channels to 960, and use the same selective calling systems.  Lots and lots of these radios around, likely in use worldwide.  31.000 MHz is one of the more popular frequencies, I've heard them down below 28.000 MHz, inside 10 meters, and on 29.750 MHz FM, 29.775 MHz FM, 29.800 MHz FM, 29.825 MHz FM, 29.850 MHz FM, 29.875 MHz FM and many others, including 30.000 MHz FM.  29.825MHz and 29.875MHz are very popular ones.  The 12.5 kHz "extra channels" aren't as busy but they are certainly in use.  I've logged 29.9375 MHz, 29.9625 MHz, 29.9875 MHz, 30.0125 MHz, 30.1875 MHz, 32.1125 MHz, 32.1375 MHz, and many many others.  Seems like the FM deviation is lowered when operating on the 12.5 kHz channels...except on some radios its not. 

59
Nice signal from the taxi lady Juanita on 26.765 MHz AM 26765kHz AM 26.7650 MHz AM late this morning (U.S. East Coast). 

SIO 333 or so at 1555 UTC / 1600 UTC or 1155 / 1200 noon local time.  Local receive in Richmond, Virginia.

Checking the W3HFU and N1NTE SDRs, her transmitter seems to be a bit more off frequency than usual...carrier offset 26764.4 kHz 26.764.4 MHz.  On the N1NTE SDR, one of the drivers replying to the taxi dispatcher is off-frequency in the other direction, carrier on 26765.6 kHz. 

Of all the Spanish language taxi cab radio systems operating in the 25-50 MHz range, this one is one of the most consistent, right up there with 31.200 MHz FM 203.5 Hz PL tone and the Costa Rican taxi cab radio dispatch system out of Alajuela Costa Rica on 32.180 MHz and 32.940 MHz 77.0 Hz PL and 141.3 Hz PL. 




60
Hearing truckers on 26.735 MHz AM right now 1130 local / 1530 UTC.  Multiple carriers noted on frequency.

And yep, they're all over the band.  Some activity on 27.905 MHz AM and 27.915 MHz AM, U.S. stations, but could be base stations vs. mobiles. 

Most export rigs are 6-band radios (25.615 MHz - 28.305 MHz) with the bands labeled A-B-C-D-E-F, and a band switch in addition to the usual 40 channel selector.  There's usually also a +10 kHz switch that allows access to the 5 skipped channels in each band.

The legal CB band is "Band D", so there's more available channels below channel 1 vs. above channel 40.  Since there's more SSB activity above channel 40, it makes sense that more activity is on bands A/B/C. 

This is true for the classic export radios like the Connex 3300 series, General Lee, General HP40W, Galaxy DX29, Galaxy DX33, Superstar 3900 etc.  Some of the nicer radios like the Galaxy DX99 are 8 band radios (25.165 MHz - 28.755 MHz), either with the bands labeled A-B-C-D-E-F-G-H and the legal CB band being Band E.  Some of these rigs have a LOW BAND/HIGH BAND switch plus a band switch (A/B/C or A/B/C/D or A-D/B-E/C-F).  The Galaxy DX99 is a good example of this, with the legal CB band being High Band A. 

Other radios, like the Superstar 121, General Grant Export, Superstar GR, etc. are 3-band radios.  That is, LOW/MID/HIGH (or C/D/E).  Mid band is the legal CB band, 26.965 MHz - 27.405 MHz.  High band (Band E) is 27.415 MHz - 27.855 MHz and low band (Band C) is 26.515 MHz - 26.955 MHz. 

There are variants of the Superstar 121 that were sold to the hunting market, the Connex Deer Hunter and Connex Coyote Hunter.  The Deer Hunter is a three band radio, with the bands labeled B/C/D.  So that highest band is the legal CB band - coverage being 26.065 MHz to 27.405 MHz.  The Coyote Hunter is identical except it has four bands, A/B/C/D, you guessed it, D is the legal CB band, coverage is 25.615 MHz to 27.405 MHz.  This fits with hunters and truck drivers and other users usually using the lower channels (as there are more channels to work with - 120 channels (3 bands of 40 channels, 3 bands of 45 channels if you count the +10 kHz switch), vs. around 65 channels available on the higher bands (and more SSB QRM). 



Confusing, I know.  Extra confusing when the radio does not have a frequency counter or frequency display.  The standard 6-band 25.615 MHz - 28.305 MHz format is common enough that it's become the de facto standard. 


There are, or were, truckers involved with logging in my area that hung out on 25.835 MHz AM.  That's Channel 19 on band A.  Local operators often use their home channel up or down one band as a "secret" channel...examples include using 26.885 MHz AM instead of 27.335 MHz AM (Channel 33 down one band).  Another one is locals who use "Channel 50" (27.505 MHz AM) as a "side channel".  Of course, its actually Channel 8 up one band. 

Really helps to have a frequency display...or at least a printout of the channel plan.   

I've been listening to two groups of truckers on 26.735MHz AM as I've been typing this.  It's now 1147 local time - 1547 UTC and 26735 is very much active. 

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