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Messages - R4002

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10/11 meters / Re: 11m DX starting to roll in 1302 UTC 16 OCT 2021
« on: October 16, 2021, 1611 UTC »
Seems like Sporadic-E - hearing somebody with a thick accent on channel 38LSB 27.385 MHz LSB right now at 1611 UTC.  Heard mention of "the island"

10/11 meters / Re: Another good morning for 11m 1507 UTC 14 OCT 2021
« on: October 15, 2021, 1944 UTC »
A cursory eBay search for 6LQ6...yeah...wow. $100 for a pair of NOS tested RCA 6LQ6 tubes...others are going for what appears to be the $20-$60 per tube price range (for new in box/new old stock 6LQ6 tubes).

R/C channel (Class C) voice activity...somebody dropping a very strong carrier (S6-S7) for 10-20 seconds, unkeyed, then keyed up again...noted microphone key moving noises and then the carrier disappeared.

Probably somebody tuning up a radio or checking SWR on a "vacant" channel  ;)

W3HFU KiwiSDR, starting at 1500 local / 1900 UTC

Lots and lots of signals coming in this afternoon, within the legal CB band, including lots of SSB activity on 27.355 MHz LSB, 27.385 MHz LSB and others - and numerous SSB signals above channel 40.  Noted AM activity on 27.505 MHz, 27.625 MHz, 27.815 MHz, 27.895 MHz and a couple others.  Lots of SSB activity between 27.410 MHz and 28 MHz.

SSB signals every 5 kHz or so starting at 27.415 MHz USB

Below channel 1 - 26.715 MHz AM is going absolutely nuts right now.

Also activity on 26.305 MHz AM, 26.625 MHz AM, 26.665 MHz AM and a couple others.  CB channel 9 - 27.065 MHz AM is blowing the doors off right now (at 1915 UTC).

Spanish language - Latin American activity

10/11 meters / Re: Another good morning for 11m 1507 UTC 14 OCT 2021
« on: October 15, 2021, 1906 UTC »
I haven't talked to anyone on AM CB in years. I went from a Radioshack AM base station to a Sears Roadtalker SSB rig and eventually an HR2510 by the time I was 15. A guy I work with has a CB in his truck and told me there were still some locals on there daily. I guess it just varies from area to area. You certainly don't see nearly as many CB antennas on vehicles like you use to. Not here anyway.

Ahh, yes, the HR2510.  I remember trading a Galaxy DX 949 for one (!!) - what a great radio. 

There is a lot of variation from area to area for sure. 

10/11 meters / Re: Another good morning for 11m 1507 UTC 14 OCT 2021
« on: October 15, 2021, 1824 UTC »
11m still hopping with Latin American stations

Earlier I heard some local traffic on channel 1, it sounded like coordinated truckers. I need to check it out more often.

I heard local truckers using channel 6 (!!!) for coordination the other day...this was during a chunk of time where the band was closed though.  Usually the locals hang out on channel 4, channel 7, channel 14, channel 22 and channel 33.

Trucking companies and job site coordination on various other channels, including 12, 13, 17, 18, 20, 21, 23, 24, 25, 27, 31, 32, 35 and 36 have all been logged.  I heard two truckers talking on channel 17 the other day and they must have been running power because they were very loud for a long time..and one of them was splattering up to channel 19 (27.185 MHz) and down to channel 16 (27.155 MHz) pretty badly.  There were points where the guys on 19 had serious interference from splatter due to overmodulation from the super-loud truck driver on channel 17....

CB may be old, but it's still really popular (for obvious reasons)

10/11 meters / Re: Channel 4 FM 1845 UTC 14 OCT 2021
« on: October 15, 2021, 1812 UTC »
I am also intrigued by the FM approval.  I am also kind of surprised they didn't allow it back in the late 1990s when Europe standardized 4 watt CB (FM mode) using the same US 40-channel CB channel plan as the de facto European standard plan. 

Considering how many export rigs / 10-meter rigs are out in circulation, there might be quicker adoption of FM than you'd think.  Even the basic 240-channel 25.615-28.305 MHz exports made by Ranger/RCI - think Superstar 3000, Connex 3300, Galaxy DX 33, DX 29, dozens of others - yes, your old Dirland export rig is included in that list! - have been AM/FM radios since the 1980s.  Yes, there are/were some AM-only export rigs on the market and a few AM/SSB only ones too...must most of them had/have FM mode in addition to AM.  Even the humble Superstar 121 has FM mode. 

Of course, all the modern style Chinese export rigs have FM capability too. 

I imagine there will be an increased demand for FM add-on boards for AM only CB rigs like the Cobra 25 / Cobra 29 series and related Uniden PC66XL / Uniden PC68 series and PC76 / PC78 series...if FM takes off.  I know that AM/FM versions of bare-bones AM CB radios like the Uniden PRO510XL and PRO520XL are/were sold in Europe under the President name so it's probably not too difficult for US market versions to...well...come to market.

What I'm interested in seeing is truck stop CB shops and the various CB upgrade/tune up shops offering FM CB boards or FM mode add-on packages or upgrades / FM mods for FCC-legal 40-channel AM CB radios that are currently out there in the wild.  Turn your AM CB radio into an AM / FM CB radio!

Lots of 25 MHz and 26 MHz activity - the Mexican/Caribbean/Latin American calling frequencies, especially 26.585 MHz AM and the nearby AM channels are alive.  Some SSB activity especially on 27.455 MHz USB. 

Noted activity on the 25 MHz band including taxi dispatcher on 25.695 MHz AM

10/11 meters / Re: 11m opening 1409 UTC 13 OCT 2021
« on: October 13, 2021, 1618 UTC »
Hearing activity below channel 1 down to 25615.  Noted some AM activity on 27.545 MHz at 1614 UTC.  Also sporadic SSB signals in the 27.4 MHz to 27.7 MHz region.

Lots of AM voice activity on 26.585 MHz, 26.765 MHz, 26.565 MHz, 26.205 MHz, 26.935 MHz, 26.945 MHz, 26.885 MHz, 26.865 MHz and of course the taxi dispatcher is active on 25.695 MHz AM / 25695 AM taxi dispatcher YL and OM taxi cab company on 25.695 MHz.  One of many Latin American taxi companies and/or land mobile users on the 25 MHz band (starting at 25.615 MHz and working your way up to 26.955 MHz...). 

Lots and lots of ISM hooks on the waterfall (W3HFU KiwiSDR) as well.

1630 UTC update:

Activity on:

25695 AM 25.695 MHz AM
26105 AM 26.105 MHz AM
26175 AM 26.175 MHz AM - very weak AM signals, previously logged frequency when band is open
26455 AM 26.455 MHz AM
26565 AM 26.565 MHz AM
26575 AM 26.575 MHz AM - busy Latin American AM DX frequency (secondary to 26.585 MHz)
26585 AM 26.585 MHz AM - busy Latin American AM DX frequency
26945 AM 26.945 MHz AM - AM voice signals - possibly taxi dispatch or other land mobile users?

27440 USB 27.440 MHz USB
27445 AM 27.445 MHz AM - likely taxi cab dispatcher, some QRM with 27.440 MHz
27455 USB 27.455 MHz USB
27530 USB 27.530 MHz USB
27545 AM 27.545 MHz AM
27555 USB 27.555 MHz USB
27665 USB 27.665 MHz USB

Also of note is the fact the CB channel 5 - 27015 AM 27.015 MHz AM - is very very busy, channel 5 is one of the popular Latin American calling frequencies (for in-band operations anyway)

25695 AM - Usual Spanish language taxi dispatch lady YL - good signals
26150 FM - POCSAG - European paging pager systems
26175 AM - Spanish language
26205 AM - Spanish langauge
26225 USB - Spanish language
26250 FM - POCSAG - European paging pager systems - different data signals on top of each other
26350 FM - POCSAG and other data modes
26405 AM - Spanish language
26415 USB - Polish? or Russian language
26450 FM - POCSAG and other data modes
26565 AM - Spanish language
26585 AM - Super busy with Caribbean and Latin American stations booming in like crazy
26600 FM - Paging signals
26605 AM - SS, very busy
26650 FM - Paging and data signals
26695 FM - POCSAG - European paging signals
26745 FM - POCSAG and other data signals mixing together
26750 FM - POCSAG and other data signals mixing together 
26765 AM - SS YL taxi dispatch lady, very distinctive with roger beep
26805 LSB - "uh, behind in the mortgage" "two heart attacks and a bout of cancer"
26835 FM - POCSAG - European paging signals
26850 FM - Data/paging signals
26855 FM - Data/paging signals
26885 AM - Spanish
26895 AM - Spanish
26900 FM - Data/paging signals - POCSAG and other modes mixing together
26935 AM - SS Spanish language taxi dispatch lady
26935 FM - Paging signals - POCSAG, mixing with AM voice
26945 AM - SS Spanish language taxi dispatch lady
26950 FM - Data/paging signals, numerous signals on top of each other at points
27300 FM - POCSAG, heavy QRM from AM signals on 27.295 MHz and 27.305 MHz
27700 FM - Paging signals / data signals
27800 FM - Paging signals / data signals

Paging and data signals logged:

26150 - 26.150 MHz
26250 - 26.250 MHz
26950 - 26.950 MHz
27300 - 27.300 MHz
27700 - 27.700 MHz
27800 - 27.800 MHz

10/11 meters / FSK Bursts on 26609 USB / 26616 USB 26.609 MHz USB
« on: October 09, 2021, 2004 UTC »
Strong bursts on 26609 USB - dial frequency in USB mode...considerably weaker FSK bursts on 26615.9 USB or 26616 USB. 

10/11 meters / Re: 11M Activity
« on: October 09, 2021, 1837 UTC »
11 meters does that - I remember during the last solar peak hearing California stations working guys in Hawaii on 27025, 27085 and several frequencies around 27385 LSB.  I worked a bunch of west coast stations with a barefoot Galaxy DX 959 on 27.385 MHz LSB, 27.395 MHz LSB, and the in-between channels freqs like 27.370 MHz LSB and 27.390 MHz.  I remember hearing real powerhouse stations on 27025/27085 (channels 6 and 11 AM) - some with some really nice AM audio....lately, not so much...but there's been more propagation to Latin America, Europe and the Caribbean

10/11 meters / Re: RTTY Beacon or transmissions on 27.551 USB
« on: October 08, 2021, 1314 UTC »
Datawell Waverider Buoys







I believe that's what I heard yesterday on 27.755 USB 27755 27.755 MHz USB - center frequency seemed closer to 27.756 MHz or 27.757 MHz.

I know the Datawell HF Link is 25.5 MHz to 35.5 MHz (standard coverage) or 35.5 MHz to 45 MHz band (special request).  The 25.500 MHz to 35.500 MHz band is almost certainly the more commonly used band.  25.5 MHz to 28 MHz and 29.7 MHz to 30 MHz are probably very heavily used for these types of transmissions.  Here's another good information page on it:


The Datawell documentation indicates a 50 km range over sea using the "HF data link" 25.5-35.5 MHz.  According to the documentation for the RX-D2 data receiver for the Datawell Buoys - the frequency for the HF link is crystal controlled and the crystal is included installed from the factory - FSK data link 81.92 bits/second BCH (63, 51) error correcting code.

Receiver bandwidth: 1.2 kHz IF bandwidth, 200 Hz detector bandwidth.

Transmitter technical specifications:

The buoy transmitter converts the combined digital data stream which contains the wave height
data, wave spectra, wave direction, seawater temperature etcetera into a high frequency (H.F.)

Technical details:
The HF output signal of the transmitter is FSK modulated with a rate of 81.92 bits per second in
a bandwidth of 200 Hz and a radiated power of 75 mW (19 dBm). The transmit frequency is
crystal controlled and between 25,5 and 35,5 MHz.   

Buoy transmit antenna
The transmit antenna is the interface between the buoy transmitter and the physical channel,
namely the atmosphere.
Technical details:
A vertically polarized quarter wavelength whip with a gain of 2 dBi is used as a transmitting
antenna for the Waverider- and Directional Waverider buoys, except for the DWR-G 0.4m.
The seawater around the buoy (or an other artificial ground plane) is an important part of the
antennas counterpoise and is therefore absolutely necessary for the buoy’s transmission system
in order to radiate its power efficiently. In other words, a buoy without a high conductance
groundplane such as normal soil2 will have a severely limited range.
The transmit antenna is of an omni directional type because the rotation of the buoy is
undetermined with respect to the receiving station.

"The RX-D2 is delivered with a factory-installed receiver crystal. This receiver crystal can be
exchanged to allow reception of other frequencies within the specified frequency range (see
chapter 6).
When the frequency of the receiver needs to be changed, the recommended procedure is to send
the RX-D2 back to Datawell for exchanging of the crystal and subsequent realignment of the
receiver. Please contact Datawell sales for more information."


With these band openings...I bet we'll be seeing a lot more of these types of data link transmissions.  There are a lot of different "Class C" data link, telecommand, telemetry, paging, pager and similar systems all over the 11 meter region. 

27.255 MHz is the big one in the USA.  There are a dozen or so known active frequencies in the 26 MHz region used in Europe, including 26.945 MHz, 26.950 MHz, 26.955 MHz, 26.960 MHz (plus 26.995 MHz, 27.045 MHz, 27.095 MHz, 27.145 MHz, 27.195 MHz and 27.255 MHz). 

26.150 MHz, 26.200 MHz, 26.250 MHz, 26.650 MHz, 26.665 MHz, 26.700 MHz (offset frequencies from 26.7 MHz including 26.695 MHz are popular), 26.850 MHz, 26.935 MHz and several other frequencies are used for on-site paging, including hospital paging services...much like 27.255 MHz is used in the USA.  POCSAG paging signals have been monitored all over the 11 meter band, including on weird offset frequencies like 27.007 MHz, 27.003 MHz, 27.000 MHz, etc. 

I have personally monitored POCSAG paging signals on 27.255 MHz in the USA. 

Here is a page with information on one of the telemetry systems that use 27.255 MHz with 10 watt transmitters:



I know that there are other devices manufactured by the same company that use 26.995 MHz instead of 27.255. 


26165 AM 26.165 MHz AM - Spanish language
26405 AM 26.405 MHz AM - Spanish language
26665 AM 26.665 MHz AM - Spanish language
26785 AM 26.785 MHz AM - Unmodulated AM carrier, maybe somebody doing radio checks
26945 AM 26.945 MHz AM - Weak signal, possibly taxi dispatch YL Spanish numbers (previously logged)

27465 USB 27.465 MHz USB
27475 USB 27.475 MHz USB - Spanish language
27500 USB 27.500 MHz USB - Caribbean stations
27520 USB 27.520 MHz USB - Weak SSB signals
27555 USB 27.555 MHz USB - "calling Central America..." (in Spanish) heard at 1814 UTC
27605 USB 27.605 MHz USB - Spanish and English heard, very busy
27625 USB 27.625 MHz USB - Spanish language
27655 AM 27.655 MHz AM - Weak AM signal, possibly taxi cab dispatcher
27675 LSB 27.675 MHz LSB - Spanish language
27755 USB 27.755 MHz USB - Sounds like RTTY or maybe PSK, 27.756 MHz center frequency
27795 AM 27.795 MHz AM - Roger beeps heard
27815 USB 27.815 MHz USB - Spanish language
27835 AM 27.835 MHz AM - Spanish language

10/11 meters / Re: Lots of activity 1430 UTC 7 OCT 2021
« on: October 07, 2021, 1806 UTC »
27515 LSB often has some pretty colorful QSOs on it. 

Bonus points for when the Mexican taxi lady with the crazy roger beeps on 27.515 MHz AM is reading numbers on top of the Jamaicans

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