Toroid choke for VDSL modem

I noticed that my transmissions on 3740 kHz were often accompanied by a loss of sync on the VDSL modem that provides U-verse service to my home. This is not surprising, given the frequency spectrum used by VDSL and the proximity of my dipole antenna to the aerial service drop that brings phone service and U-verse to my home. I obtained a large diameter ferrite toroid -- FT-240-J from Amidon and installed it on the DSL line cord at the modem. The 'J' material is designed to provide excellent attenuation in the 0.5 to 20 MHz range. Below is a photo showing the installation.

This toroid is large enough to thread multiple turns of the DSL line cord with the RJ-11 plug attached. Since the toroid resolved my interference issue, I could install a smaller toroid with the RJ-11plug temporarily removed, and save the large toroid for future troubleshooting or other problem resolution.

Update 6/20/17: This toroid should be effective on higher frequencies also, up to the 20 MHz top of range quoted by Amidon. At my past QTH I needed this toroid for 75 m only. 40 m and 20 m were not affected. At my present QTH the VDSL modem was replaced due to a lightning surge, and the new modem was not susceptible to interference. 

Hurricane Irene's Track

On 8/22/11 I saved a screen shot of the forecast model tracks for Hurricane Irene. See below, and click on the image to enlarge.

It is interesting to compare this with the actual track of the storm as shown below.

Of the various forecast models, the NGFDL seemed to have a good fit as the storm approached North Carolina, while the GFS had a good fit during the later path of the storm. According to what I saw on TV, the model tracks were all pretty close together as the storm traveled up the east coast. Naturally, small changes in the track's position east or west made a big difference in storm surge at the local communities on the coast.

Note that 8/29/11 was the 6th anniversary of Hurricane Katrina's landing on the coasts of Louisiana and Mississippi.

Lumens per Watt

Lighting technologies on today's consumer market span a wider range of choices than ever. As we migrate toward better energy efficiency, new metrics come to the forefront to help with decisions about what to buy. With the advent of compact fluorescent lamps (CFLs), the actual light output in lumens became an important characteristic for comparisons, since their power consumption in watts is considerably less than the power required by standard incandescent bulbs. Product specs and advertising are now including lumens per watt as a measure of efficacy, to indicate the amount of light produced with the power consumed by the device.

Many web pages now include tables that list this measure along with the actual light output and power required for a given lighting technology or device. For example, see this one from a utility company. A similar table appears in the middle of Home Depot's main page about light bulbs.

A review of such tables shows that incandescent bulbs trail the pack at only 10 to 17 lumens per watt. Fluorescent devices are much better, in the range of 30 to 110 lumens per watt. LED devices are shown in various tables and past web articles as being in the range of 20 to 60 lumens per watt. However, the LED technologies are improving rapidly. One of the companies actively developing this technology has reported achieving 200 lumens per watt. Another company making progress on the price is discussed in the article:
Silicon Is Key to Quest for $5 LED Lightbulb.

As noted in the article LED Lighting: Blue + Yellow = White :
"One of the goals of the U.S. Department of Energy's 2010 solid-state lighting road map calls for more than doubling the lumens per watt in commercial LED products by 2015."


Currently available LED devices are pricey, but moving lower, and are not yet at efficacy levels that surpass linear fluorescent bulbs. It should be noted, however, that linear (tube) fluorescent bulbs diminish in brightness with age and are usually specified with their beginning-of-life brightness. Also, the efficiency of the fluorescent fixture ballast is not necessarily included in the specs for the bulbs. And remember that fluorescent bulbs contain mercury. Be sure to recycle them.

A common application example may provide additional appreciation for the device specs. My friend Larry has a workshop that is illuminated using four twin-tube 48" fluorescent fixtures. Assuming 40-watt T12 bulbs and using the data from Home Depot, these fixtures would produce 8 x 2600 = 20,800 lumens and consume at least 320 W. If the same lumens were to be produced using common 100 W incandescent bulbs (1180 lumens each), there would be 17.63 bulbs, consuming 1763 W. One currently-available LED spotlight could provide 1100 lumens with only 15 W. Power for the 19 needed bulbs would total 285 W, but the cost is prohibitive -- $798. When LED devices are commercially available at 200 lumens per watt, the total power requirement for Larry's workshop would be 104 W.  Clearly it is not economical for Larry to replace his full set of fluorescent bulbs with LED devices at the present time. New construction, especially commercial, should look closely at using LEDs, however. The economics of using currently-available LED bulbs in place of incandescent bulbs and CFLs are discussed in the article: The Lightbulb That Really Is a Better Idea.

Hopefully, as incandescent bulbs vanish into history, LED devices will become more plentiful and less expensive so that we can enjoy better lighting efficiency while avoiding the toxic characteristics of fluorescent bulbs.


John

Updating Vulnerable Software

There is no end in sight to the parade of malware exploits that make use of vulnerabilities in popular Windows-based programs. If you are not sure of your system's vulnerability or don't trust the automatic notifications that you receive from some programs, you should consider running a scan on a regular basis to determine what programs need to be updated. Two facilities that I have used and trust are:

• FileHippo - You can download popular program updates from their home page, or install and run their free Update Checker for a scan of the most popular programs installed on your PC. You can choose to have it run every time you start Windows or just run it on demand. The results are displayed on a convenient web page where you can click and download any updates you need or want. They include beta versions of programs that you may or may not want to use. This scanner identifies version updates for a select group of popular programs, not every program installed on your system. The updates are not all associated with patching security holes. Below is a screen shot fragment that shows the scan results I obtained today. Click on the image for a full-size view.

• Secunia Online Software Inspector - This scanner concentrates on identifying vulnerable programs on your PC. It also provides a web page report with links to the updated program versions. It is a Java applet and so requires Java to run. Below is a screen shot fragment that shows the scan results I obtained today. Click on the image for a full-size view.

Scanning takes only a few minutes on most systems. Downloading and installing the updates may take some time, especially if you have many outdated programs, but all experts in the field of computer security agree that patching vulnerabilities is very important to the overall secure use of your computer.

PC Software Upkeep

Our recent morning QSO on 3740 kHz included some discussion of software maintenance on Windows-based PCs. The most important reason for this task is to avoid software vulnerabilities that can provide opportunities for criminals to take control of your PC, either for extracting your personal information or for using your PC in criminal activities, or both.

We all recognize the need to use and regularly update anti-virus programs. Since no anti-virus program detects every instance of malicious software, you may consider occasionally running supplemental scans with other programs. However, you should avoid installing multiple anti-virus programs as they may conflict with each other. Malwarebytes Anti-Malware has a free version that I've found to be very effective in removing malware on some friends' and relatives' PCs that had other well-known anti-virus programs installed. You may also consider running Spybot Search & Destroy. Note that serious malware infections may require much more aggressive software tools and techniques, up to and including clean installation of the operating system!

Anti-malware programs should not be relied upon for complete protection. Software updates are often issued to patch vulnerabilities that criminals are exploiting to gain access to computers. FileHippo has a very nice free update checker, a small program that you can download and run to check many of the commonly used programs installed on your PC to find out if updated versions are available. If you'd like a more thorough scan of many more programs installed on your PC, specifically for vulnerabilities, try one of the two free consumer products from Secunia.

Many web sites offer free or shareware programs that appeal to PC users' wants and needs. Purveyors of malware can also use their own (or compromised) web sites to push their programs. Here are a few trusted web sites where you can download free or shareware programs:
cnet download.com
FreewareFiles.com
FileHippo.com
One example of a popular utility program available on these sites is CCleaner. I like to use it periodically on my PCs. The publisher's web site encourages you to purchase the program or make a donation, but you can download a free copy from FileHippo or from a separate link on the Piriform web site.

When installing programs that you download, be sure to pay attention to various options presented during the installation. Some programs will have options pre-selected to install extra web browser tool bars or extra software that you probably don't need. Many programs will pre-select an option to run automatically every time Windows starts. You may want to de-select that option to avoid burdening your CPU with too many things starting and running all the time.

News about PC software and security can be found at many web sites. You may consider visiting some of the following to see which ones you might want to check on a regular basis:
Krebs on Security
cnet
Kim Komando
PC World
MakeUseOf
ZDNet
ars technica
There are MANY more to choose from.

Finally, be sure to use caution in your Internet usage to avoid the risks that exploit human carelessness and gullibility. See the following sites for well-written guidance:
OnGuard Online
GetNetWise
These two sites are well-suited for sharing with your family members and friends.

More update sources about Japan's nuclear power plants

Here is an excellent summary provided by the New York Times. Thanks to Jorge for sharing this one!

Lots of detail is available at the web site of the Japan Atomic Industry Forum. New PDF documents are published frequently. Much of this is probably more than you want to know, but you may like the map shown on page 5 of update #43. The map shows the location and status of all nuclear power plants in Japan.

Also, NOVA on PBS will feature a special program, Japan's Killer Quake, on Wednesday, March 30 about the earthquake and tsunami.

NOVA will also investigate the future of alternative and renewable energy, including nuclear, in Power Surge, premiering Wednesday April 20.

Two articles of particular interest to me, from IEEE Spectrum's ongoing coverage:

• Fukushima's Impact on Nuclear Power
  A summary (with many links) of how various countries plan to alter or sustain their nuclear power plans 
• Nuclear Reactor Renaissance
  Seven contenders for new reactor designs

Japan's Nuclear Power Emergency

Some recent discussions among my friends have shown the need for more information about Japan's damaged nuclear power plants and the reasons for the escalating crisis. Some very good sources of more detail than what's presented by the mainstream media include the following: 

• Fukushima Nuclear Accident – a simple and accurate explanation
  Has a good explanation of the reactor design and operation, with multiple update links
• Explainer: What Went Wrong in Japan's Nuclear Reactors
  Thursday's update to an ongoing series by IEEE Spectrum
• Japan Earthquake and Reactors in That Region
  Ongoing information from the Nuclear Energy Institute

The operating reactors were, of course, immediately shut down when the earthquake occurred. A Wikipedia article defining reactor SCRAM explains how a reactor core is very rapidly shut down from operating power levels. Based on my experience aboard U.S. Navy nuclear submarines, this shutdown can be executed automatically, according to certain operating parameters, or manually by the human operators. I believe that commercial nuclear power plants are operated in the same manner.  

After such a shutdown there is continued production of decay heat at a much lower level, but this heat must be removed to prevent core damage. For a reactor operated at steady power for an extended period, the decay heat production is initially as high as 6.5% of the reactor's initial operating power. After one hour the decay heat drops to about 1.5% of the initial operating power. Decay heat decreases with time, as described in the article linked above. After one year the decay heat from spent fuel generates about 10 kW of heat per metric ton (of fuel). 

The crisis at the Fukushima Daiichi plant was intensified by the inability to reestablish full electrical power to operate the cooling systems for decay heat removal. A very concise likely timeline of events is presented in this article. 

I suggest consulting the above referenced sources for further updates as the efforts continue to gain the upper hand in controlling the decay heat following unprecedented forces of nature. 

Let us also focus on the much broader human suffering that is the direct result of the earthquake and tsunami. 

Webmail Address Book Bloat

Users of some webmail programs find that their address books or contact lists may become bloated with many email addresses they did not intentionally add. This is usually the result of an option in the webmail program's settings to automatically add all recipients' email addresses to the sender's address book or contacts list. For a one-time or infrequent original or reply email, a sender may or may not want to add the recipient to his or her address book.

Shown below are screen shot fragments that illustrate where to find the applicable option for the webmail clients of AT&T Yahoo email and AOL/AIM email. Click on each image for a larger view.

AT&T Yahoo Email

AT&T Yahoo webmail inbox showing Options link

Where to pick More Options

Where to find the applicable option

 AOL / AIM Email

Inbox showing link for Settings

Where to find the applicable setting

 
Another source of address book clutter relates to spam filtering. When an email program has identified an email as possible spam by tagging it or placing it in a user's spam folder, a webmail user may designate a desired email as not spam. Some webmail programs will then add the sender's email address to the reader's address book so that future emails from that sender are not treated as spam.