Wednesday, August 6, 2008

40M Phone, I'll believe it when I see it.

Better Days Ahead for 40-Meter Phone
A new U.S. 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 hams know, 40-meter phone at night can be horrible in the U.S. phone band because of the ear- piercing interference from foreign broadcast stations. Many of their signals are strong enough to nearly peg our S-meters and if music is broadcast, it can seemingly splatter across large segments of the band.

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 us 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 Regions 1 or 3, you can operate from 7000 to 7200 KHz.

I can't wait.

73, Dave, N4KZ

FROM K1TP'S PAGE "AS THE WORLD TURNS"

I remember how 40m was totally trashed. Including down into the so called Amateru
Exclusive below 7100. The band was useless for ham use except for CW. And that
was clobbered by SWBC.

In Europe it was DAY and Night, Thus I hardly bothered to operate 40 as DA2LJ.

What I'm saying is those SWBC didn't care to follow the ITU then, and I'll believe
it when I see in now.

Dan/W4NTI

2 comments:

Anonymous said...

I'll believe it when I hear it as well. :)

Anonymous said...

Back in the Cold War days, I remember Radio Moscow World Service broadcasts were all over 40 meters at night.