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December 30th 09, 07:40 AM
posted to rec.radio.shortwave
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Can't get much on Shortwave.
On Dec 29, 10:09*am, "Geoffrey S. Mendelson"
wrote: Ric Trexell wrote: I only have a portable shortwave radio (Grundig Yacht Boy 400) that I have had for about 15 years. (It replaced a Grundig 2000 which was a real nice radio in its day.) *When I first got it there was stuff on there not only in the bands but in between. *There were about 10 places to hear the BBC and VOA. *Now I can tune the radio all night and maybe pick up a few Christian broadcasts and one or two Spanish stations. *I usually just end up listening to the AM and FM stations. *Even Hams are sort of rare. *If this keeps up, in a year or two there won't be anything on SW. *Or is there something wrong with my radio? *Ric in Wisconsin. No, there are several things that have happened. One is that shortwave radio signals bounce off the top of the athmosphere (the ionosphere). That's why you can hear them being too far away for ground wave signals (the ones that travel along the surface of the earth). The number one thing that controls the ionosphere is the sun. When there is sunlight, the ionosphere bounces higher frequency radio signals, which is why some bands work better during the day and others at night. The second thing is the number of sunspots. The more sunspots the more the ionosphere is "charged". Sunspots follow an eleven year cycle, 15 years ago we were just ending a peak. Now we are at the bottom of a cycle. This bottom is rare, there have been so many months with no sunspots and so little recovery that it may be the worst cycle since people have been keeping track (1700's). Things are so bad that many people are predicting another "little ice age" (look it up). So radio propigation (the spreading of signals) is much less than it was 15 years ago, and the frequencies that spread are much lower. The next problem is noise. I live in a medium sized city (Jerusalem). All around me are computers, wireless networks, telephones, etc. This puts me in a cloud of electrical noise that covers over radio signals. 4 mHz and below is unusable to me. That's how I tell if an (infrequent) power outage is just my building, or the entire neighborhood. If I can receive the BBC on 1323kHz (AM broadcast band) from Cyprus with a portable radio, the outage is more than just right around me. If you have a radio tuned to it an on when the power is restored, you can hear the devices all starting up. Things have also changed with shortwave broadcasting. Between the internet, satellite delivery of broadcast material, and paid subscriptions (NPR pays the BBC to give you BBC news) stations are abandoning North America. Signals are still out there, but in a lot of cases you are not getting them beamed to you directly, you are hearing a signal aimed at someone else. These signals are much weaker and you may need a better radio, a better antenna or more patience to receive them. Since the end of the cold war, political broadcasting almost stopped. Radio Moscow, Radio Habana (Cuba), and the soviet satellites dropped or reduced their programing. The US policial stations (VOA, Radio Marti, Radio Liberty, etc) scaled back their programming or left the air entirely. In that area things are changing. China (the PRC), Russia (now a rising world power trying to fill the vacuum), and so on are hitting the shortwaves big. However they are not going after you, although programs aimed at the developed countries are broadcast, but they deliver over the internet too.. The reality of the situation is that no matter how what people can use to get their information, nothing is as hard to stop, or as cheap to receive with no infrastructure than shortwave boradcasting. I'll bet as I write this, (Dec 29, 2009) there are a lot of people in Iran who wished they had shortwave radios. Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel *N3OWJ/4X1GM New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or understanding, as in he has a sub-wikipedia understanding of the situation. |
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