10.542 USB at 02:18 UTC Mexican Fishermen

[HF DXER]

Mexican fishermen talking about various fishing topics, life and throwing in some foul language. Good signal into the wes coast. They mentioned Ensenada port.
Is 10.542 a maritime hf channel or are these pirates.

[R4002]

10.542 MHz USB 10542 kHz USB is not a legal marine channel / frequency.

10542 kHz USB is used by the Civil Air Patrol - channel/frequency designator "NET 7".  It also apparently used by the Russian Navy.

As far as the frequency itself, it falls within the Fixed/Mobile Service allocation, specifically the 10150 kHz - 11175 kHz band or 10.150 MHz to 11.175 MHz band.

https://www.hfunderground.com/wiki/index.php/Fixed/Mobile_bands

^Link for more information.  The fixed mobile bands are used for...well, everything.

Here are the (legal) MF / HF SSB marine bands (often just called "HF marine" even though there is a considerable amount of activity in the 1.6 MHz to 3 MHz range, which is technically MF, not HF - but for practical purposes, 2-30 MHz is called "HF" - although some equipment manufacturers do 1.6 MHz to 27.5 MHz instead of 1.6 MHz to 30 MHz or something along those lines.   

https://www.hfunderground.com/wiki/index.php/HF_marine#MF_SSB_and_HF_SSB_marine_bands

Closest maritime mobile service allocations are the 8 MHz marine band and the 12 MHz marine band.

8 MHz band - maritime service 8195 kHz - 8815 kHz or 8.195 MHz to 8.815 MHz. 
8 MHz band - shared with fixed/mobile service 8000 kHz - 8195 kHz or 8.000 MHz to 8.195 MHz

12 MHz band - maritime service 12330 kHz - 13200 kHz or 12.330 MHz to 13.200 MHz. 

Both the 8MHz and 12MHz bands are pretty extensively used, as are the 2-3 MHz band, the 4 MHz band and the 6 MHz band. 


6 MHz band 6200 kHz to 6525 kHz or 6.200 MHz to 6.525 MHz is also used for numerous other purposes.  The lower portion especially is used for shortwave broadcasting.

4 MHz band 4063 kHz to 4438 kHz or 4.063 MHz to 4.438 MHz.  The 4000 kHz to 4063 kHz fixed mobile band is also used for marine purposes on a shared basis.  4.000 MHz to 4.063 MHz.

2 MHz band allocation varies from country to country:

2000 kHz to 2300 kHz
2450 kHz to 2850 kHz

The 2850 kHz to 3155 kHz band (2.850 MHz to 3.155 MHz) and the 3400 kHz to 3500 kHz (3.400 MHz to 3.500 MHz) bands are both allocated to the aeronautical service (aircraft radio) but both of those bands widely used for marine purposes too.  The 3155 kHz to 3200 kHz band is allocated to the fixed mobile service, but many marine users simply use the entire 1.6 MHz to 4 MHz band, or the 1.6 MHz to 3.5 MHz band 1600 kHz band to 3.500 MHz band for marine purposes. 

The 1610 kHz to 1800 kHz band is used for marine purposes rather extensively outside ITU Region 2.  It is also used for fishnet radio bouys, along with the larger 1.6 MHz to 4.0 MHz band and the 25 MHz to 30 MHz band, including the 26 MHz - 28 MHz CB allocations and the 28 MHz - 29.7 MHz 10 meter ham radio (amateur radio) allocation.

2000-2300 kHz   MF 2 MHz marine band - USB voice calling/distress 2182 kHz, DSC calling/distress 2187.5 kHz - USCG no longer monitors 2182 kHz USB
2450-2850 kHz   MF 2 MHz marine band, USB voice and FSK modes, some AM voice heard here in Russia, Eastern Europe and Asia (older-generation trawler radios 2-4 MHz AM mode, many users operate outside this band, roughly around 3 MHz)