I noticed something last week where a new U.S. licenced ham recently posted a question on eHam about operating on 40-meter phone. At night, he said, he only hears strong shortwave broadcast stations and very few hams. Don't hams operate on 40-meter SSB at night, he asked? That's a good question and, fortunately, some relief is on the way for 40 meters -- in just a few months. And the change to 40 meters should be rather profound worldwide.
As experienced ham operators know, 40-meter phone at night can be horrible to work because of the ear- piercing interference from foreign broadcast stations.
But some relief is on the way. As of March 29, 2009, foreign shortwave stations broadcasting on 40 meters between 7100 and 7200 KHz are to cease. They will be permitted, however, to continue using 7200 to 7300 KHz. So, that will free a 100-KHz portion of the band from the terrible interference those high-powered stations generate. As such, the 40-meter band will double in size for many of the world's hams.
At present, the band is just 7000 to 7100 KHz in much of the world. (Quite a few countries have already given their hams early permission to use the band above 7100 KHz.)
The 40-meter situation -- with shortwave broadcast stations sharing the band with hams -- has a long and complex history. But here is a short version. Prior to 1938, 40 meters was a worldwide ham-only band from 7000 to 7300 KHz. But in the years leading up to World War II, some governments began pushing to use part of 40 meters for broadcasting. Why? It's prime shortwave real estate and as the world would soon discover, they had war on their minds and wanted good propaganda outlets via shortwave radio. Hence, they obtained international permission to broadcast on a portion of 40 meters provided they did not interfere with hams in North and South America, which comprise Region 2. None of them ever took the non-interference issue seriously and hams in North and South America got stuck with terrible interference and the hams in Europe, Africa, Asia and the Pacific, Regions 1 and 3, lost their use of 7100 to 7300 KHz as a result.
This injustice was partially rectified five years ago when the World Radio Conference voted to evict the broadcasters from 7100 to 7200 and return that portion of the band to hams in Regions 1 and 3. This has no direct impact on us in Region 2 other than after March 29 of next year, the band from 7100 to 7200 KHz should be free of foreign broadcast stations and all the interference they generate. Although many hams around the world will probably continue operating SSB below 7100 KHz -- as they do now -- many will certainly move up into the U.S. phone band above 7125 to work americans simplex instead of operating split frequency.
Just imagine -- ragchewing at night on 40-meter phone between 7125 and 7200 without BC interference? Or working DX stations right on your frequency without having to listen down below 7100. Or, if you're in Region 1 like me or even in Region 3 , you can operate from 7000 to 7200 KHz.
I can't wait.
4 comments:
Well its now April and March 29th has come and gone. I have been enjoying SOME DX on 40m but, thanks to the non-compliant Chinese BC stations we here in the US have about 20Kc to work with in the new 7100 to 7200 allocation. Chinese BC at 7200 spills down to 7190, combined with Chinese BC this morning at 7187 thats 20kc wide, same at 7170, 7140 20kcs wide and 7127 20kcs wide...there isnt much room left for DX SSB. The other problem we have here is the east coast and midwest rag chewers get into section of the band that isnt occupied and cover up DX stations that are located between 7170 and 7150.
When will the damn Chinese vacate 40m? Similarly, when will be rid of the Chinese radar that shuts down ALL of 75 meters?
Still waiting for the "Better Days Ahead for 40 meter band" here in California.
Yes, 40 meters is like a new band now. Lots of DX to be had in the 7100-7200 range, with world wide coverage. There are a few rogue BC stations left, but most of the spectrum is untouched. Fantastic!
As WB3HUZ said, 40m is like a new band.
But I still hearing some broadcasters, specially an asiatic station at 7105 kHz.
I think they are transmiting illegally.
How can we report it?
Who is the responsible of controlling this? I think it is ITU.
LW7ELK
PS: If you know how to report OR denounce this, you can contact me at (my call) at gmail
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