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Messages - R4002

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Maybe there's a loose connection between when they're on the radio and which frequency they're using.

There's gotta be some method to this madness...

If you don't mind me asking, what receiver(s) and antenna setup do you use for monitoring 225-400 MHz? 

I have a feeling they’re within groundwave range of each other too, considering the time of day they’ve been heard.  Maybe they’re right outside of regular old VHF marine band range, or maybe they don’t want their conversations on the regular VHF marine band. 

Interesting about the selcall use on 6925 kHz....I wonder where those guys are now!  Maybe they’re up above 40 meters.  There’s a lot of Spanish speaking traffic (in both USB and LSB) in the 7300 kHz to 8000 kHz range, peppered in-between broadcast signals and other stuff...then up into the legit 8 MHz marine band. 

So we know they use 6212, 6095, 6870 and a couple frequencies in the 69xx range too, right?  I remember hearing fishermen with New England accents on 6953 kHz and 6959 kHz...not sure if they were the same guys though.  Considering the sheer number of antennas you can see in Gloucester harbor alone...there’s gotta be other users on HF. 

Before I visited Gloucester I visited Portland, Maine and took a tour on a lobster boat.  Being a coastal-only boat they were only VHF / VHF-DSC equipped.  I spoke with the captain about radio stuff, he remarked how his fleet’s bigger boat had a “long range SSB radio” (HF) in addition to VHF radios.  The Portland harbor had countless HF and VHF antennas on both the fishing vessels and fishery buildings on-shore.  VHF channel 16 was very active...the Coast Guard would often tell vessels to switch channels if they started actually having a QSO on VHF 16. 

Too bad the Glocestermen aren’t using SELCALL or another system that we could ID them with.  I bet they are using driftnet radio buoys or fishnet radiobuoys...maybe a listener closer could hear their low-power signals (assuming they’re using ones in the 1600 to 4000 kHz range and not the 26 to 30 MHz range or SATCOM based).

Just had some chatter on "Magnum 5", 357.050 MHz 1904Z 17JUL19

Awesome.  Glad those air-to-air or interplane frequencies are proving fruitful for you.  Similar informal CB-like chat? 

Interesting.  Have you noted any identifiers of any kind when hearing these guys?  I've only listened to them a handful of times and no callsigns have been heard.  FWIW, 6212 kHz is ITU 6 MHz marine channel 605.  It's listed as a duplex frequency (for ship-to-shore anyway, paired with 6513 kHz...with 6212.0 kHz being the "ship transmit" frequency).  With that in mind, it makes sense for them to use it as a simplex frequency for ship-to-ship comms.  Apparently this is pretty common practice.  Since their SSB radios likely came pre-programmed with all the ITU marine frequencies out of the box, that would also make sense. 

My bet is 6212 USB is their official or home channel, and the various other 6 MHz frequencies we've monitored them on are side channels, "secret channels", alternate frequencies, etc. etc.   As I mentioned in the other thread, during my recent visit to Gloucester, MA, I did notice many of the fishery buildings had HF antennas on their roofs.  Maybe 6212 is their "company channel" and the other frequencies are used so the boss-man and/or other ships in their fleet can't listen in? 

As an aside, the majority of ITU marine frequencies (channelized HF marine band plans for 2 MHz, 4 MHz, 6 MHz, 8 MHz, 12 MHz, 16/17 MHz, 18/19 MHz, 22 MHz and 25/26 MHz) involve duplex pairs.  Only the following frequencies are explicitly designated for simplex ship-to-ship or ship-to-shore use - specifically SSB voice:

2 MHz (2000 kHz - 2850 kHz) marine band:

2003.0 kHz
2065.0 kHz
2079.0 kHz
2082.5 kHz
2086.0 kHz
2093.0 kHz
2096.5 kHz
2142.0 kHz
2203.0 kHz
2214.0 kHz
2635.0 kHz
2638.0 kHz
2738.0 kHz
2782.0 kHz
2830.0 kHz

4 MHz (4000 kHz - 4438 kHz) marine band:

4146.0 kHz
4149.0 kHz
4417.0 kHz

4000 kHz to 4060 kHz are also designed for simplex maritime radio use, in 3 kHz steps (4000 kHz, 4003 kHz, 4006 kHz, etc.), shared with fixed/mobile service

6 MHz (6200 kHz - 6525 kHz) marine band:

6224.0 kHz
6227.0 kHz
6230.0 kHz
6516.0 kHz

8 MHz (8000 kHz - 8815 kHz) marine band:

8294.0 kHz
8297.0 kHz

8101 kHz to 8191 kHz are also designed for simplex maritime radio use, in 3 kHz steps (8101 kHz, 8104 kHz, 8107 kHz, etc.), shared with fixed/mobile service

12 MHz / 13 MHz (12330 kHz - 13200 kHz) marine band:

12353.0 kHz
12356.0 kHz
12359.0 kHz
12362.0 kHz
12365.0 kHz

16 MHz / 17 MHz (16460 kHz - 17360 kHz) marine band:

16528.0 kHz
16531.0 kHz
16534.0 kHz
16537.0 kHz
16540.0 kHz
16543.0 kHz
16546.0 kHz

18 MHz (18780 kHz - 18900 kHz) marine band:

18825.0 kHz
18828.0 kHz
18831.0 kHz
18834.0 kHz
18837.0 kHz
18840.0 kHz
18843.0 kHz

22 MHz (22000 kHz - 22855 kHz) marine band:

22159.0 kHz
22162.0 kHz
22165.0 kHz
22168.0 kHz
22171.0 kHz
22174.0 kHz
22177.0 kHz

25 MHz (25070 kHz - 25121 kHz)

25100.0 kHz
25103.0 kHz
25106.0 kHz
25109.0 kHz
25112.0 kHz
25115.0 kHz
25118.0 kHz

I put together the list above as these frequencies are also likely to be pre-programmed in MF / HF SSB marine radios, in addition to the dual-use duplex/simplex channeling (3 kHz steps for SSB voice, except odd steps on 2 MHz band).  It should also be noted that many older-generation SSB marine radios do not cover the higher bands.  Many radios only cover up to 12 MHz / 13 MHz or 16 MHz / 17 MHz. 

Peskies / Re: 5555 KHz LSB 16 July 2019 0210Z English
« on: July 17, 2019, 1304 UTC »
Any mention of fishing or boat-related matters?  Could be freebanders or out of band ham operators.  The frequency choice (5555 kHz) is popular with both freebanders/outbanders and fishing fleets.  They like easy to remember frequencies (for example, 6666.6 kHz USB is very popular with Latin American freebanders).

**EDIT**      I modified the title to show just July 2019 VHF / NOAA Weather Radio ducting discussion





From this morning, roughly 0645 to 0655 local time (US east coast), I was able to hear activity on all 7 NOAA Weather Radio NOAA WX frequencies, with all except the local station having multiple signals at once.  162.400 and 162.550 seemed to have three stations going at various points.   The band does appear to be open to one degree or another every morning, but this morning was an extreme example. 

Spy Numbers / Re: Numbers stations
« on: July 17, 2019, 1238 UTC »
Spies Like Us was actually funded by the CIA as part of a recruitment project.  Regardless, it’s a hilarious film.

Also, thank you for the PDF link.  This is a great read.

Other / Re: 7050 6855 7500 LSB
« on: July 17, 2019, 1234 UTC »
Are the Russians transmitting on 6850 kHz, 6855 kHz or 7500 kHz in addition to the usual 7050 kHz and 7055 kHz frequencies? 

Awesome work, will have to put them into scan. These are kinda similar to the hf channel that used to get more USAF activity than it does now, 6761. That freq was treated like a party line for bombers, tankers, everyone.

On the presets, these vary according to the unit, each craft of a given unit will have the same presets.

Neacp/tacamo/glass flight burning mux on 338.950MHz 1929Z 16JUL19

I’ve heard chatter on 6761 kHz USB a few times too.

In a weird way, it’s like the pescadores and freebanders on HF.  They like easy-to-remember frequencies.  343.400 MHz, 6666.6 kHz, 6363 kHz, 40.40 MHz, 30.30 MHz, 45.45 MHz, 7676.7 kHz and so many others come to mind. Frequencies like 123.450 MHz and 246.800 MHz are super easy to remember.  Same with the often-overlooked 137-144 MHz and 148-150 MHz VHF bands (25 kHz steps, shared with military users using FM and P25 digital in 12.5 kHz/25 kHz steps). 

I know the Air National Guard in my area uses 140 MHz and 141 MHz freqs (in AM mode) in addition to the usual UHF band frequencies, plus a couple FM tactical band channels (namely 38.500 MHz, 38.550 MHz and 49.725 MHz, I presume there are others I don’t know about) for air to air chatter.  The National Guard also appear to use over a dozen different repeated frequencies in the 148 to 150.8 MHz range for tactical comms, only instead of AM or FM voice, they use encrypted P25 digital voice (12.5 kHz channel steps). 

Oh, also 282.800 MHz - aka “Hard Luck” - which is also the search and rescue/survival radio alternate frequency to 243.000 MHz.  I imagine use of 282.8 MHz for air to air chat is frowned upon, but yes, you’ve got some hard luck if you have to use your survival radio....

I don’t know how many scanner channels you have to work with Josh, but here’s another “button” list for the USAF, apparently used for “auxiliary” purposes, such as air to air chat maybe.

265.500 MHz - “Button 1”
266.600 MHz - “Button 2”
267.600 MHz - “Button 3”
268.600 MHz - “Button 4”
269.900 MHz - “Button 5”
270.100 MHz - “Button 6”
271.600 MHz - “Button 7”
272.700 MHz - “Button 8”
273.500 MHz - “Button 9”
274.800 MHz - “Button 10”
275.800 MHz - “Button 11”
276.400 MHz - “Button 12”
277.200 MHz - “Button 13”
278.400 MHz - “Button 14”
279.400 MHz - “Button 15”
280.500 MHz - “Button 16”
281.200 MHz - “Button 17”
282.800 MHz - “Button 18”
283.000 MHz - “Button 19”
284.200 MHz - “Button 20”

Good signal on the Westminster, MD KiwiSDR, thanks for the weekday show! 

With the tell-tale insanely awesome big bandwidth and audio.

Mix Radio International on 49 meters!  6019 kHz USB 6.019 MHz USB

I did some Googling and apparently there are several of these frequencies in use for air-to-air chat, similar to the way civilian pilots use 123.450 MHz and 123.475 MHz.

They include, but aren't limited to:

234.500 MHz - "Straight"
234.550 MHz - "Straight 5"
299.500 MHz - "Cheap Suit"
300.600 MHz - "Thirty aught Six"
303.000 MHz - "Thirty Thirty" "Winchester" or "Three Oh Three"
303.050 MHz - "Winchester 5"
333.000 MHz - "Triple 3”
333.300 MHz - “Quad 3”
333.550 MHz - “Full House”
345.600 MHz - "Straight" (see also: 234.5 MHz)
351.000 MHz - Haircut
357.000 MHz - "Magnum"
384.500 MHz - "Pistol"
399.950 MHz - "Penthouse"

It seems like specific units have others, often nearby these (for example, there's a "Magnum 5", 357.050 MHz), and others.  Of course, there are the specific units' present channels, often referred to us "push 3" or "button 3" for preset 3, for example.  There's also the 137-144 MHz and 148-150 MHz ranges for AM air to air voice. 

As close to frequency as practicable

So basically, these aren't rules, they're more like guidelines.

303.000 AM 1859Z 12JUL19
"We told them to order enough pizza for 8 people"


Is 303.000 MHz akin to 123.450 MHz on the VHF air band?  Sort of the air-to-air chat frequency?  I can see who it would be easy to remember - 303.000 = "thirty thirty" or "three oh three"?   I bet 345.600 MHz, 357.000 MHz, 308.000 MHz and similar are also used? 

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