General – Page 50 – Engineering Radio

Solar flare may disrupt radio systems

Update: What? Nothing Happened! Something I think any radio engineer can appreciate, the incoming magnetic field from the flare was not polarized for maximum effect. According to NOAA Space Weather Prediction Center, the incoming particles were parallel to the earth’s magnetic field, and thus blocked. In order for storms to have major effects, they need to be cross-polarized with the earth’s magnetic field. Learn something new every day.

On February 15 at 01:50 UTC, a massive flare erupted from the sun. Classified as an X2.2 storm, it is the largest since December 2006. The 2006 storm disrupted GPS, and some satellite signals and caused 950 mHz STLs to burp occasionally. With all of the cellphone systems synced to GPS, not to mention things like HD Radio exciters, it could be an interesting day. Or not. Already, some reports are trickling in from southern China of communications disruptions.

According to NOAA Space Weather, there is a 45% chance of geomagnetic activity starting on Thursday, February 17th. It is noted that Geomagnetic storms reaching the G1 level and radio blackouts reaching the R1 level are to be expected. Mid to high-level latitudes may see extensive aurora borealis, which will be visible in spite of the full moon.

ABC turns to HF during tropical Cyclone

Super Tropical Cyclone Yasi, a category 5 storm, came ashore this morning between Cairns (pronounced Cans) and Townsville, Queensland around midnight Thursday (9 am Wednesday, NY time).

Radio Australia carried Australian Broadcasting Company (ABC) Queensland coverage of the storm, which was extraordinary. Spot coverage, emergency information, sheltering information, updates, and calls from listeners in the midst of the storm. Some of it is pretty intense. One fellow, John, out in the country all by himself in the height of the storm sounded somewhat forlorn, I hope he makes it.

Due to the size of the storm, widespread power outages are expected and may last for weeks or months. As a part of this, there are numerous outages and potential outages in their AM and FM broadcasting chain. To that end, ABC has two shortwave frequencies available for their Queensland service; daytime (8 am to 8:30 pm local time, 2100 – 0830 GMT) on 9710 KHz and night time (8:30 pm to 8 am local, 0830 – 2100 GMT) is 6080 KHz.

Once again, HF (shortwave) radio gets the job done when local stations, cell towers, and internet connections to dead. Sometimes it is the low-tech answer.

Egypt demonstrates why the Internet is unreliable

On Thursday, January 27th at 22:34 UTC (about 4:30 PM, NY time) Egypt cut off outside access to the internet. According to Renesys:

At 22:34 UTC (00:34am local time), Renesys observed the virtually simultaneous withdrawal of all routes to Egyptian networks in the Internet’s global routing table. Approximately 3,500 individual BGP routes were withdrawn, leaving no valid paths by which the rest of the world could continue to exchange Internet traffic with Egypt’s service providers.

Go and read the entire article. Notice how the government asked and the ISP corporations complied. This is in response to massive riots and uprisings in Cairo and other cities which may topple the government. Think that the internet and new media alone can keep our government honest and doing the people’s work? Think again. Net Neutrality is a pipe dream and would do nothing to stop this type of censorship regardless.

A free press is one of the critical legs of our democracy. Traditional broadcasting and media have been decimated in the last 15 years. They are not without fault, cutting staff, politically slanted reporting, and profit-taking has done their part. Fortunately, while staff have disappeared, the infrastructure (networks, transmitters, printing presses) remains in place. They need to be revitalized and utilized. There is a trend that I and others have noticed where small operators, perhaps one or two stations at most, are providing excellent service to their respective communities and running circles around other, group-owned stations in the same market.

Medium Wave List

This is an excellent data base of LW and MW worldwide: www.mwlist.org

According to the website:

This is a radio station database of all Longwave (LW), Medium wave (MW) and Tropical bands stations worldwide. You can browse frequency and location lists, search for stations, and get technical information. If you register, you can use a online logbook, create bandscans, and provide update information to the database editors. This is a free, open and non-commercial hobby project which depends on the cooperation of many individuals.

For LW/MW DXer’s this is a good information source.