Author Topic: 6220 USB Spanish Language Marine Freebanders 2148 UTC 14 April 2018  (Read 54 times)

RobRich

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They are inside the 6MHz marine spectrum, but not using a designated marine channel. One guy sounds like he is practically inside the engine room. o.0
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R4002

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The bottom portion of the HF marine band seems to be another place where these freebanders like to hang out.  They like easy to remember frequencies (think 6767.6 kHz, 6886 kHz, 6666.6 kHz, etc).  Since most of the radios these operators use have displays that read 12.345.6 MHz or 12345.6 kHz that makes sense.  I have heard marine traffic on 6220 kHz USB before but I presumed it was legit marine traffic and not freebanders. 

However, it appears that you're right.  6220 kHz isn't a legal HF SSB marine simplex or SSB marine duplex frequency.  ITU marine duplex channelization is as as follows for that region:

Channel 606 - Coast TX 6516 kHz - Ship TX 6215 kHz (also simplex - 6215 kHz is the 6MHz distress frequency)
Channel 607 - Coast TX 6519 kHz - Ship TX 6218 kHz
Channel 608 - Coast TX 6522 kHz - Ship TX 6221 kHz

Simplex channeling:

Channel 6A - 6224 kHz
Channel 6B - 6227 kHz
Channel 6C - 6230 kHz

So 6220 kHz USB is just above ITU SSB marine channel 607 and just below channel 608.  Of course these are free-VFO radios in addition to having the ITU channels in them...and I've heard all sorts of simplex ship-to-ship comms on the "ship transmit" side of the duplex channels so that's not that surprising.  As far as I can tell, the 6 MHz marine band 6200 kHz to 6525 kHz is supposed to be mostly duplex operations (compared to 4 MHz and 8 MHz which are home to lots and lots of simplex ship-to-ship comms). 

Silly to expect freebanders to follow any sort of rules regarding channelization/channel steps or frequency split.  Better they hang out in quiet portions of the marine bands or the upper parts of 6700-7000 kHz than the busy 6 MHz aeronautical band!

shadypyro

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Wonder if i can pick that up now there's a SDR from Yucatan Mexico? I will give it a try..
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R4002

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I'd be interested to see what else that SDR can hear/see.  Could you PM me the URL for it?


shadypyro

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I'd be interested to see what else that SDR can hear/see.  Could you PM me the URL for it?

I PM you the URL for it.
Tecsun PL-380, Sangean ANT-60 Portable Shortwave Antenna.