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Messages - Exo

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Lately, I've been hearing more truckers using FM on Channel 24 (27235 kHz) and none on Channel 29.
Maybe all the bleedover from 28 AM made them find the new channel.

Channel 19 AM on the West Coast has remained in active use as a trucker and highway information channel since about 1976.
Prior to that, Channel 10 AM was the ad hoc nationwide trucker channel, but some regional trucker channels (such as 17 AM and 21 AM) also existed then. 

Channel 17 AM started as one of those regional trucker channels in California.
Then 17 AM became very active up and down the coast around 1978 during the intense skip of that roaring sunspot cycle.
Eventually, around 1996 during the low point in the sunspot cycles, most truckers in California began keeping their dial locked on 19 AM instead of switching to 17 AM when they were on Interstate I-5.
17 AM eventually stopped being a trucker channel at all, and devolved into a calling and working channel for the locals in many California towns and cities.

The addition of FM to the new FCC rules will probably cause another evolution in the use of FM for truckers and local information.

The growing use of Channel 29 as an FM Trucker Channel looks eerily similar to the way previous trucker channels evolved.

It appears from their chatter that some truckers may be trying to claim CB Channel 29 as their new "trucker FM channel".
Perhaps that's just local to the west coast.
Also heard weak signals, distinctively FM activity, on 27295.0 when the skip was in to the plains states earlier today.

That makes sense though.  Do they still use channel 17 and channel 21 on the West Coast in addition to 19?  Here on the East Coast its 19 but I could see Channel 29 FM as the trucker FM channel being adopted nationwide relatively quickly. 

Goes to show how many trucks are equipped with export rigs with AM and FM capability.   

I just updated the first post in this thread to reflect the use of CB channel 29 FM 27.295 MHz FM 27.295 FM as the trucker FM CB channel.

It appears from their chatter that some truckers may be trying to claim CB Channel 29 as their new "trucker FM channel".
Perhaps that's just local to the west coast.
Also heard weak signals, distinctively FM activity, on 27295.0 when the skip was in to the plains states earlier today.

There's a lot of truckers using Channel 29 FM 27295 kHz.

Have they been using FM on Channel 29 for a while now?  Or is CB channel 29 FM a new thing like 26.805 MHz FM? 

I kinda like it - CB Channel 19 AM, Channel 29 FM.  Makes sense to use 27.295 MHz (channels 27 and 31 also make sense - in-between the "big radio" channels 26/28 27.265 MHz AM and 27.285 MHz AM) for FM CB. 

Glad to see the surprisingly rapid adoption of FM. Since there's a vast installed equipment base capable of FM mode already out "in the field" the switchover from AM/SSB to AM/FM/SSB CB radio / 11 meters is already happening. 

For short range comms, FM provides superior audio quality and rejection of noise/static.  When dealing with weaker signals, AM has some advantages but SSB is the obvious winner in those situations.

I had included 27.315 FM CB channel 31 - 27.315 MHz FM as the FM CB calling channel since CB channel 31 FM is one of the European in-band FM calling channels, I would call it the European version of 27.385 LSB channel 38 LSB but for FM mode specifically and for calling specifically. FM is the "default" mode for CB in many European countries so the situation is reversed. 

In the UK, for example, AM has only been legal on the FCC 40 CB channels or mid band CB or CEPT/EU standard 26.965-27.405 MHz band for the past 10-15 years.  SSB was legalized even later.  On the UK specific UK FM CB 27/81 channels 27.60125 MHz - 27.99125 MHz, FM is the only mode permitted and that probably won't change. 

Most European countries permit AM on the standard 40 CB channels in addition to FM (and most of those allow SSB as well) but this is somewhat recent of a development.  Now basically all CB rigs sold in Europe are AM/FM at least.  In many ways, the FCC legalizing FM on CB is sort of things coming "full circle".  AM will still be the standard mode for US CB radio - SSB and FM are now the extra-feature modes but I can see FM-capable FCC approved CB equipment entering the US market rapidly.

There's a lot of truckers using Channel 29 FM 27295 kHz.

HF Beacons / Re: The Desert Whooper
« on: August 26, 2021, 0110 UTC »
The Desert Whooper,

Thank you very much for the wonderful e-QSL card!
The Desert Whooper is by far one of the strongest and most interesting HF beacons of its kind that I've copied in the past decade here.
The use of CW telemetry for temperature, power, and solar charge status is brilliant.
Best wishes.


Thank you very much for the detailed report along with the picture and audio recording! You must have a low noise floor there. Great audio quality and quite a thrill to hear the Desert Whooper through your SDR

The eQSL will be in your PM inbox in a minute


HF Beacons / Re: The Desert Whooper
« on: August 24, 2021, 2313 UTC »
"The Desert Whooper HF Beacon"

Frequency: 4095.65 kHz
Mode: CW
Date Time: 2021AUG23 2206UTC
Signal level: -102 dBm, good readable.
Copy: DW  BAT 13.6  OTMP 98  ITMP 114  PV 4  DW
Notes: Upward frequency chirp signature whoop only on repetitive dash intervals.

PLAY MP3 audio recording of Desert Whooper HF Beacon reception

Waterfall display image on my kiwiSDR receiving Desert Whooper HF Beacon

Receiver: my home kiwiSDR on the coast of Northern California.
Antenna: Broadband dipole at 30ft.

HF Beacons / Re: 5295.0 AM Ten Count Beacon
« on: August 21, 2021, 2227 UTC »
Yes, it really is quite an unusual beacon, even more so if it turns out to be an HF pirate beacon.  :o

This was 5 MHz in the middle of the day, while propagation below 6 MHz was limited to only regional NVIS and without any distant DX propagation happening.
At first blush it seemed like it could be a new or unknown numbers station, so I hit the record button.
It might be good to continue to watch for it.   8)

Yes, there have been some other HF voice beacons, tests, or markers in the past... but not many pirate HF voice beacons.

It possibly could have been sent by a ham transceiver running a vox memory function, but the carrier appeared keyed prior to modulation rather than VOXed.
The precise timing makes it appear more likely to have been developed with a computer generated sequence.  ???
Yet another possibility, is that this is a little known transmit self-testing function built as a standard feature into some new asian-designed marine or commercial transceiver.

That unusual EE asian voice tonality pitch and asian-accented number pronunciation, could either be a clue or misdirection.
PLAY AUDIO of the 5295 AM Ten Count Beacon, listen to pronunciation of figure 5 and 7 in the test count.

Amazing catch! That would win the prize for Very Very Unusual Beacon.  ;D  Thanks for the recording!!

Has there ever been a voice driven pirate beacon before? Any old timers know?

Honestly not sure if it can be called a pirate beacon just yet but hopefully it comes back on the air for further analysis!

Did the synthesized voice sound Australian to anyone else?    ::)

HF Beacons / 5295.0 AM Ten Count Beacon
« on: August 20, 2021, 2241 UTC »
5295.0 kHz AM Synthesized Voice Beacon "Ten Count"

2130UTC 2021AUG20 started logging of an unknown AM voice transmission already in progress.
Signal approximately -95dBm with fading, weak readable.
2159UTC 2021AUG20 noticed that this beacon ceased abruptly in a mid-transmission.

PLAY AUDIO of the 5295 AM Ten Count Beacon

This UNID HF beacon or test transmitter was heard transmitting a series of repetitive sequential transmissions.
Some occasional gaps were heard between the repetitive sequences, which were about 3 to 7 transmissions in each sequence.
Each Transmission Duration: 10 sec.
Each Transmission Repetition Rate: 20 sec.

Sequence timing of each transmission was approximately as follows:
Carrier On, Silence for 500 mSec.
AM Modulation Beep Tone 440 Hz for 370 mSec.
AM Modulation by synthetic Asian male accented voice type EE (English), "Testing 1-2-3-4-5-6-7-8-9-10" for 8.2 sec.
Silence for 500 mSec, Carrier Off.
Repeat at next 20 sec clock.

Appears to be standard AM (Amplitude Modulation) with both sidebands.

Estimated area: West Coast of North America or Eastern North Pacific.

2020 NOV 30 0400UTC
5377.7 kHz USB voice
Asian language fishing fleet, likely S. Korean.
4 or 5 stations.
Approximate location today: a few hundred miles off the coast of Oregon and California.
Often heard nightly 0400-0530UTC spinning big fish stories to each other on this frequency.
Motors and other industrial ship background sounds.

Note: this isn't a normal Maritime HF channel or band

Propagation / Re: Here's our pre geomagnetic storm foF2/MUF boost
« on: September 28, 2019, 2335 UTC »

It provided some really good transequatorial propagation and F2 openings on 27 and 28 MHz.

HF Mystery Signals / Re: 8956khz Aug 4 02:37utc
« on: September 27, 2019, 0024 UTC »
No, almost certainly not an OTHR.

Yes, agreed, it isn't OTHR.
Also agreed, it looks like a sweep tone within a standard 3 kHz or 2.8 kHz speech communication bandwidth.
The curious discontinuous wiggles in the sweep frequency might be some kind of data, or be just a glitch.
That makes it interesting. 

Other / Re: 5690KHz Japanese/English voice tx
« on: September 22, 2019, 2032 UTC »
This is an international standard "Aero Off Route" channel.

Generally open Aeronautical freq, but usually not LDOC or RDARA or MWARA.
It can be utilized by all types of aircraft and air-ground or aero comms orderwire (private, corporate, mil) entities.
Most of the "Aero Off Route" channel allocations are well known for mil air.

Other standard "Aero OR" channels may be found at 3.0 kHz intervals up from this channel.
5680 international AERO SAR channel with Maritime SAR interoperability (+/-4 kHz protection)
5684 "Aero Off Route"
5687 "Aero Off Route"
5690 "Aero Off Route"
5693 "Aero Off Route"
5696 "Aero Off Route"
5699 "Aero Off Route"
5702 "Aero Off Route"

Equipment / Re: Test Equipment for First Time Build
« on: September 13, 2019, 1849 UTC »
A calibrated radio receiver.

Other / Re: 57530 LSB 08:51z automatic laser gun firing sound w
« on: September 10, 2019, 0544 UTC »
Automatic laser gun, firing sound, with a beep beep beep.

Google OTH Radar and CODAR.

Equipment / Re: Inverted sloper?
« on: September 06, 2019, 1634 UTC »
Put the feedpoint up as high as possible.
If one end is higher, make it the "hot" side.

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