Wednesday, March 25, 2009

Handiham World for 25 March 2009

Welcome to Handiham World!

Cartoon guy with white cane & dogFree software tour: Two screenreaders

Last week we talked about the free rig control program called HRD, or Ham Radio Deluxe. Today, I want to share a couple of free screenreader solutions for our members who are blind or have low vision.

In my opinion, there was never an area in the world of software solutions that is more worthy than providing affordable computer accessibility. While I understand and respect the need for professional-grade assistive-technology software, the business needs of commercial producers are such that the end product can be very expensive. This will inevitably shut out many users who simply cannot afford hundreds, or perhaps even thousands, of dollars for assistive technology software above and beyond the cost of their computer systems. A business or educational setting may require commercial software with its superior performance and customer support. On the other hand, home users can be well served by free software solutions, whether they are free software that you download and install on your computer or web-based. I am going to give you links to what I feel is the best free software screenreader as well as an online screenreading resource operated by a nonprofit organization. Neither one will cost you a dime, and both are very capable screenreading resources.

Thunder: This is a free screenreading program that you download and install on your computer. You will need Microsoft Windows, 2000 or newer. The website does not specifically state that Vista is supported, but we believe that it is. Lists of keyboard commands are available for Thunder, as you would expect for a commercial product. The Thunder screenreader website states in large, bold type:

Thunder is TOTALLY FREE to all organisations and all individuals.

No, they didn't spell organizations wrong; that is the British spelling! Thunder is used worldwide, and the organization that offers it is in Great Britain. If you already have a commercial screen reader on your computer, you should stick with what you have, because we do not recommend installing two screenreading programs on a single computer.

The AIR Foundation, or Accessibility is a Right Foundation: this nonprofit organization offers free screenreader access via the Internet. You open up the organization's website, and immediately it will begin talking to you and telling you how to use the screenreader. Once it is running, you need to stay connected to the Internet and as long as you do so, you have free screenreader access on your computer. It's as simple as that; you really don't need to know very much about either operating a computer or screenreaders to make this thing work. We have not tested it on a dial-up Internet connection, but we strongly suspect that it would not work. We suggest either a DSL or cable modem connection to the Internet.

The AIR Foundation is a not-for-profit organization, whose mission is to advocate, teach, and deliver tools that promote accessibility as a fundamental human right. Its first corporate partnership is with Serotek Corporation.

Where to find these resources: Go to the Handiham website at handiham.org, where you can read the entire issue.

Wednesday, March 18, 2009

Handiham World for 18 March 2009

Welcome to Handiham World!

Ham Radio Deluxe main screenFree software tour: Ham Radio Deluxe

Last week we talked about the free audio editing program called Audacity. Today, I want to tell you about a wonderful way to control many modern amateur radio transceivers using a personal computer. This information pertains to users of Microsoft Windows because the software is written to run specifically on that operating system. Ham Radio Deluxe is a free software suite written by Simon Brown, HB9DRV.

Ham Radio Deluxe (HRD) also includes mapping, satellite tracking and the digital mode program Digital Master 780 (DM780). It is designed for Windows 2000 or higher (XP, Vista, 7), also Internet Explorer 6.0 (or higher) is required. It may work with Windows 98 but this is not supported. The policy is to support Windows versions which are supported by Microsoft.

Any licensed Amateur may download, install, and use HRD. It is not open source software, however. The difference is that the software author does not license the software under an open source licensing agreement, and the computer code is not public.

Before I get into any details about Ham Radio Deluxe, I think we should make it clear that this software is constantly under development and is thus being improved all the time. It has gone through many releases and upgrades over the years, and I have used it with great success in my own ham shack for many of the years that it has been available. The fact that HRD is always in active development sets it aside from many other software packages. Oftentimes you will find that a rig control program has maybe one or two releases, and not very much changes, if anything, after that. Ham Radio Deluxe is different, because it keeps getting better and better. I like the fact that I don't have to worry about ditching my rig control program because it is hopelessly out of date. This is one of the most important reasons to choose Ham Radio Deluxe.

In order to use software to control your radio, you will need to provide a hardware connection between the radio and your computer. How you do so depends on which radio you have and what kind of ports your computer has available. Fortunately, there is information on the Ham Radio Deluxe website that will help you get this part of the job done. In the case of my ICOM IC-706M2G, I learned that I needed a special cable. This was relatively easy to find at a good price via the Internet. Further connections were done via a commercial rig interface, in this case a Rigblaster. I found that it was easiest to follow the Rigblaster instructions and everything worked pretty much as expected right away! You may find satisfaction in building your own interface, and you will find plenty of help for doing so on the Internet.

Ham Radio Deluxe should be downloaded and installed after you get your hardware connections in order. I won't go into detail, but HRD will prompt you for the proper port settings the first time you use it, and after that the computer will remember all of these details so controlling your rig will be as simple as turning on the power to the rig and then running Ham Radio Deluxe.

Like many hams, I have a few frequencies and modes that I return to on a daily basis. Generally speaking, most users will find that they do not take advantage of the many features of HRD. For example, I will typically use HRD and my ICOM to check into a local HF net, PICONET, once in the morning and once in the afternoon. The net meets on 3.925 MHz SSB, and Ham Radio Deluxe allows me to save that frequency and mode into my "favorites". A simple click of the mouse puts me on the PICONET frequency. Since I like to keep a record of stations that I have worked, I use the logbook feature in HRD. The logbook is a pop up window that has all of the basic input fields you would expect, but what makes it easy to use is that all I have to do is enter the net control station's callsign, and the log book remembers the station and allows me to choose "auto fill" to complete all the other fields with the correct information about name and location, as well as a note that this was PICONET. The frequency field always reflects the radio's true frequency, which is sent by the data cable from the ICOM to the computer.

If you like DX, there is a DX spotting window built into Ham Radio Deluxe. A list of DX spots appears below the frequency screen, and all you have to do is click on the DX spot you're interested in, and the radio automatically changes frequency to the same one as the DX station. I am not much of a DX chaser, but I do enjoy using this feature to see which bands are open. Since the DX spotting feature gets its information constantly from the Internet, you need to have a live Internet connection. You do not need an Internet connection to use HRD to control your radio, as long as the radio is connected through an interface directly to your computer. However, it is also possible to control a radio remotely via the Internet using Ham Radio Deluxe. I have enjoyed using the K0LR IC-756 Pro transceiver located in northern Minnesota, even though I was physically located in Gulf Shores, Alabama. Lyle and I set up the details for me to log on before I left for vacation. Since I was already familiar with controlling my radio with HRD, it was easy to learn how to control another radio remotely via the Internet.

Even so, I feel as if I have barely started to use all of the features Ham Radio Deluxe has to offer. You can run digital modes, track satellites, map the contacts you are logging, operate CW, display a short wave station database, and customize the program to your liking. Since I can see the computer screen, I do not use the built in voice to speak frequency and mode, although these features are available in Ham Radio Deluxe. It is worth noting that the spoken frequency is not dependent on any voice module being installed in the rig. Even if the transceiver does not have a voice module, HRD can still speak the frequency. That said, what I have heard from blind hams is that HRD is not all that blind-friendly from the standpoint of screen reader users. I would like to get more detail on what features are accessible and which ones are not. Since this software is supported by an excellent team of volunteers, perhaps one day accessibility improvements can be made.

You can get Ham Radio Deluxe by following the kink on the Handiham website.

Next week: Two free screen readers.

Patrick Tice, WA0TDA
Handiham Manager

wa0tda@arrl.net

Wednesday, March 11, 2009

Handiham World for 11 March 2009

Welcome to Handiham World!

Free software tour: Discovering Audacity

Audacity screenshotIt has been a relentless winter here in the Northern Hemisphere, so I thought it would be nice if we all took a bit of a holiday. I can't afford a real holiday, but how about a tour? A virtual tour of some of the best free software I have discovered over the years might be just the thing to help us make the last dregs of winter go down a little easier!

Audacity: No, I am not talking about the kind of audacity than means being bold. This Audacity is a free, open-source audio recording program for your computer. It is cross-platform, which means that you can use Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems to run Audacity. The reason I want you to discover Audacity is that you will learn to use a powerful recording tool, your computer, and learn to work with new recording technology. If you have been frustrated as I have been over the years by broken cassette tapes, the impossible situation of finding a place in the middle of a cassette, editing tape audio, annoying tape hiss, and all the rest of the problems that go along with analog tape recorders, you know what I mean.

In this edition of your weekly Handiham World I am going to give you some basic tips about how to find Audacity on the Internet. Some of you will be brave enough to download and install Audacity and give it a try. Others may be interested in learning more about basics of audio recording using a computer. Either way, I would like you to take a look at the Audacity website and then let me know if you are interested in learning more about recording audio, audio editing, and converting one kind of audio to another. The reason I am asking this question is that I am contemplating doing a series of tutorials covering this topic. If there is enough interest out there, we will cover it in some depth.

Read more at handiham.org.


Wednesday, March 04, 2009

Handiham World for 4 March 2009

Welcome to Handiham World!

cartoon runnerEMF - Run for the hills, it'll get you!

EMF - electromagnetic field - is a physics term, one that amateur radio operators know about, perhaps not in those very words, but from their studies for licensing examinations they know that magnetism and current flow are related. A flow of electrons through a conductor creates a magnetic field that is strong in the vicinity of the conductor, but falls off rapidly as distance from the conductor increases.

Even though we can't see an electromagnetic field, it is a real physical field produced by electrically charged objects, and we can measure it with various instruments. A simple one is a compass, the needle of which will move when it is in the vicinity of a conducting circuit hooked to a battery. This is a simple experiment done in elementary school science classes.

Both AC and DC produce EMF. Some devices, like your simple doorbell, depend on the magnetic field generated in a coil when a doorbell button closes a switch that allows current to flow. The magnetic field pushed an iron rod into a piece of tuned metal that makes the ding-dong sound. Some appliances around the home use motors that require much more energy to do work, such as running the compressor in your fridge or moving the fan blades in your furnace. The more current that flows, the stronger the EMF, most of which is contained within the motor and the appliance cabinet.

Ham radio equipment generates EMF, too, but much is at radio frequencies, as you would expect! There will be other electromagnetic fields around power supplies and other accessories. Even the desk lamp on the ham shack desk and the wiring inside the walls of the house have electromagnetic fields surrounding them.

In short, we are bathed in EMF from almost everywhere!

Now, with all of that in mind, let's look back a couple of weeks into the news. At the University of California in San Diego there is an ongoing flap over a cancer cluster in a single campus building. The gist of the story is that the Literature Building is suspected of having cancer-causing EMF because a larger than expected number of cancer cases have shown up among people who work or have worked in that building. I'll give you the link to the story on the campus newspaper website after this story, but for now, let's look a little more closely at what has happened at the campus.

The facts are these:

  • There are electromagnetic fields in the UC Literature Building, as there are in every campus building.
  • There are elevators in the building, and the motors that run them generate electromagnetic fields.
  • A number of workers in the building have indeed been diagnosed with cancers of various types over a period of years.
  • There is a cluster of cancer cases, given the way one maps out the parameters over time and space.
  • The issue is an emotional one that has generated demonstrations, marches, and anti-EMF activism among faculty and students.

But what do you think? As ham radio operators, we certainly have an interest in a story like this!

Should we be worried that EMF will give us cancer? It sure seems that some of the students and faculty members at the University are worried enough to take action, even to the point of demanding that the entire building undergo a renovation.

Well, here is what I think: Sometimes people get an idea into their heads and even though it is not strongly supported by empirical evidence, the kind of evidence that good science demands, they still believe that they are right. Something like EMF is a good candidate to pin an otherwise unexplainable cluster of cancer cases upon, especially since it is invisible and possibly mysterious to those who are not educated in the sciences. Remember, mankind has a long and sad history of blaming natural events on something like the position of the planets in the sky! Malaria was once thought to be brought on by swamp air. Gemstones had the power to protect you against diseases; emerald protected the eyes. Disease and causality were simply not understood, and the germs that caused many diseases were invisible, just like EMF.

Today, people still fall prey to the same mistake of associating two independent events and assuming that one causes the other.

Now, I am not going to say that EMF in extremely high concentrations or over long periods of time is perfectly safe. I am also not convinced that the cancer cluster in the Literature Building has anything to do with EMF. Did the two exist together? Yes. Are they connected? Maybe, but maybe not.

Cancer clusters are little understood by laymen, and even educated residents of a college campus can make mistakes interpreting what seem to be straightforward facts. After all, the thinking goes, there were many more cancer cases in the Literature building than one might expect by sheer chance. Something caused them, so it must have been EMF, because it acts in mysterious ways, not fully understood, upon the body.

The problem is that cancer clusters are not necessarily a statistical anomaly at all. Try this: Think of a grid of 100 squares, such as a perfectly flat tile floor in your kitchen. Now you pour an entire jar of 100 marbles out onto the floor from as high as you can reach. The marbles will bounce around at random and eventually come to a standstill, distributed across the entire kitchen floor. Look at each square tile. Does each tile have exactly the same number of marbles on it? Not likely! Some tiles will have none, most perhaps one or two, and one tile may have a half dozen. Now, imagine that the tile with a half dozen marbles is the Literature building. What "caused" the marbles to stop in that particular tile? After all, the average number of marbles on a tile is only one. Something must have "caused" the marbles to concentrate there, right?

Wrong.

Pure, random chance is in play here. Nothing "caused" the concentration of marbles on that particular tile, just as a tile with no marbles was not "protected" from marbles by some unseen force. So cancer clusters can be random. The fact that there are electromagnetic fields present in the Literature Building may be no more relevant than the color the walls in the Literature building are painted. It would be astounding if your 100 marbles distributed themselves exactly one per tile on the kitchen floor, and so it is with real life geographic distributions.

It is easy to be tricked by this phenomenon. Our minds work to seek out cause and effect. We want to know a reason why things are as they are, but every cluster does not mean there is a cause related to anything other than chance.

As an amateur radio operator, I know that electromagnetic fields are generated by my equipment. Some of these are proven dangerous, such as high power, concentrated microwave energy. But I am not going to worry about the EMF from my refrigerator or an elevator motor. I am going to take prudent steps to reduce RF exposure. I don't worry about getting cancer from a cell phone or handheld radio, but I do wear a seatbelt when in an automobile and hold the railing while using the escalator or taking the stairs. Ham radio isn't going to give you cancer, but you could fall off the tower while putting up an antenna. Take stock of reasonable risks and prepare for them. Use a safety belt and hard hat when doing tower work. And enjoy getting on the air.

I don't want to dismiss the very real concerns of the UC San Diego students and staff, but I do think that it does not serve a useful purpose to fixate on electromagnetic fields as "the cause" of a cluster of cancers. It will be interesting to follow this story as it unfolds. I prefer to be open-minded. If empirical evidence exists outside of random chance, it is important for us to learn about any effects electromagnetic fields have on the body.

Now, as I promised, here are some links you can use for further reading: