Wednesday, March 30, 2011

Handiham World for 30 March 2011

Welcome to Handiham World!

Strap on your tool belt! We are jumping right into...

Troubleshooting 101 continued: "My antenna is generating electricity and giving me shocks!"

Small tools and wire

Recap: Last week we presented the following scenario and invited comments:

We are going back in time to when I worked at an antenna company, a job that often involved talking directly to customers on the phone. I would answer questions and make suggestions about installation and troubleshooting. One fine day we got a call from a fellow who had installed one of our vertical antennas. He had ground mounted it, carefully following the instructions in the manual. This antenna came with an aluminum mounting post that was dug into the ground and usually secured with a bag of do-it-yourself concrete mix. A fiberglass dowel in the exposed end of the mounting post served as an insulator and supported the vertical element of the antenna. The center conductor of an included length of a matching section of 75 Ohm coaxial cable was connected with a stainless steel bolt to the main radiating element and the braid was connected to another stainless bolt on the grounded mounting post as well as to a ground rod within inches of the antenna base. The customer had to supply the remaining run of 50 Ohm coax from the ham shack out to the antenna and connect it to the already installed matching section with a barrel connector. When the customer called us, he complained that his antenna was generating electricity and giving him shocks. He noticed this as he was trying to connect the two pieces of coax together.

Can you guess what was wrong and suggest what questions I might have asked the customer to verify my theory? For bonus points, what did I have to tell him to resolve the problem?

I got some good comments back from you, so it's time to share your brilliance in troubleshooting with our readers and listeners:

From Tom, WA6IVG: Unless he'd driven the antenna's mounting rod into a buried power cable, (unlikely) the problem just about has to be bad station ground. Ask exactly what the coax run is connected to, and how said equipment is grounded. If the station isn't closely connected, with heavy wire or braid, to the electrical service ground, or better yet to a separate ground rod and said service ground, then that's what to do. Also check that power main connections are two standard 3 prong grounded outlet boxes. In a totally desperate situation, of 2 prong power, maybe reversing 2 prong cords could provide a temporary, unorthodox solution but bad idea. If all is claimed to be as it should be, then his station and antenna must be on 2 different continents.
From Mike, KJ6CBW: The customer was getting shocked when connecting the long run of coax to the 75-ohm run from the ground-mounted vertical that has its coax braid connected to ground rods. The two coax cables are at different ground potentials. I think the most likely cause is that the station is not grounded because the power line isn't grounded or a 2-wire plug is being used where a 3-wire plug is appropriate. Another possibility it that the ground rods at the antenna intercepted a buried telephone line or cable-company cable, which make the antenna ground different from that of the long coax. Please don't shoot me, I'm new at this. ..!
And fasten your seatbelt for this one from Kevin, [formerly: N1PKE ]: I have been pondering your *Troubleshooting 101, query, supra, and have attempted to extrapolate a scenario that would lead to such a conclusion as that of getting poked with an electrical current while I was hooking-up my antenna feed-line connections; wherein initially, I would cast basic common-sense to the literal wind, and just to make sure that things were to be a little more interesting, I would wait until the middle of the frigid winter season, for a night when there was very little light and there was then, e.g., currently, a frozen sleet / snow storm with full-gale winds occurring; just to make sure that Mr. Murphy would have all of the available advantages to be had, at his disposal; oh, and I would purposely plug-in and turn-on, e.g., charge my electrical circuitry with an electrical current, just to make sure that if anything went horribly wrong, that it would be the last time that I would ever have to address such a problematic situation. After all, why would I want to abrasively clean-up & 'tin' any of my integral and important electrical connections? I simply would refuse to apply any dielectric dope-grease and/or silicon caulk to any of my in-line electrical components and/or fixtures; and, as a matter of establishing a ground, I would first, have several-hundred yards of my fertile, composted soil removed, and then replaced with several hundred yards of coarse beach sand, just to make sure that I had an earthen environment that promoted instability of antenna constructive support and near zero ohms of conductivity. In this way, I would have assured myself, of having an almost completely isolated radiating antenna element, that I could then have used to have my soaked, limpid corpse hung-up on, as an object lesson for folks whom mistakenly believed that incessant adherence to safety considerations were foolhardy ruminations to be utilized by keenly sensitive brainiacs, wherein, I would think that I would in the future, be included in a list of: "DO NOT TRY THIS AT HOME or ANYWHERE ELSE Listings", those listed, right next and/or near to, my newspaper obituary listing!

I think I got it right?

Wow, those are all great comments. Of course the antenna didn't "generate" electricity. Our wise readers and listeners know that the difference in potential exists when all pieces of equipment in the station and out at the antenna are not at the same ground potential. One of the first questions I asked the customer (knowing about the possibility of that ground potential problem) was whether he had unplugged the station equipment in the ham shack from the AC power mains. He had not, and because the station was not properly grounded, there was a potentially dangerous voltage difference between the plugged-in radio and the grounded antenna. I felt that he was lucky not to have been electrocuted! Kevin's "Do not try this at home" applies here for sure. Always disconnect equipment from the AC mains before doing any service on your antennas and feedlines. This is especially important to remember as we get warmer weather and our thoughts turn toward doing some of that antenna work we have been putting off during the cold winter months. And I mustn't forget: Although I do ground my station equipment, I never trust the ground to protect me. I always disconnect the power before working on the antenna system, because I know that a grounding system might fail. There is no sense taking unnecessary risks when you are working around any kind of electrical equipment.

Another thought that was brought up is the possibility of a ground rod hitting a buried power cable. The way to avoid that problem is to be sure that your antenna site is clear of underground utilities. Find out from your utility company what number to call to set up a free inspection and marking of your property so that you will know where underground lines are buried. Here in my area we have a single number to call and they send out a worker to mark underground lines like gas and electric with spray paint right on the ground over the lines. "Gopher State One Call" is our system, but you will have a similar service in your area. Be aware, though, that such services will not let you know about things like the location of underground lawn sprinkling systems that are not part of the utility system.

Since the antenna in question was a vertical, one has to be especially careful assembling it on the ground and then swinging it up into place on the mounting post. You have yourself a 26 foot long aluminum stick and you are holding it with both hands, so you most definitely do not want to swing it up into a power line! Since my caller was in fact alive to call and tell me that his antenna was "generating electricity", I pretty much assumed that he didn't make that particular mistake. Direct contact with even a household power line in such a situation is often deadly because the current will flow from power line to antenna through the victim's arms and through the chest cavity, where it will likely cause the heart to stop or go into arrhythmia.

Anyway, when you are answering customer complaints like this one, the most likely cause usually turns out to be the right one. He had indeed left the rig plugged into the AC mains and was getting a shock because of some fault in his equipment or station ground.

Stay safe and out of the obituaries!

Wednesday, March 23, 2011

Handiham World for 23 March 2011

Welcome to Handiham World!

Butternut vertical covered with snow.

The power of ice combined with wind is evident once again! As those of us whose antennas have had to weather many winters can tell you, there is little worse for an antenna system than ice combined with wind. I was reminded of this earlier today when I opened my email and found a message from AA9BB in Lacrosse, Wisconsin. It had a link to a story about the 2,000 foot WEAU TV transmitting tower that collapsed near Fairchild, WI during the ice and wind storm that moved through last night. We are still having a pretty terrible Spring blizzard from the same weather system here in the Twin Cities. Fortunately no one was hurt in the tower collapse, which was only discovered when the station engineer paid a call to the transmitter site to determine why the station had gone off the air. While there will obviously need to be an investigation into exactly why this tall tower fell, my money would be on the wind and ice combination causing the design limits to be exceeded.

When the wind blows, most amateur radio antennas will not be damaged. Wire antennas have little wind loading area, and beam antennas are made to flex in the wind. The problem comes when weather conditions are just exactly right to allow freezing rain to fall and turn to ice upon hitting the ground or your ham radio antenna. The extra weight of the ice can be several times the weight of the antenna itself, putting considerable strain on the supporting system components like insulators, guy wires, masts, and towers. This is bad enough, but then suppose that the wind picks up. As storm fronts move through, the weather conditions will change. There can be periods of regular rain followed by freezing rain as the temperature plummets, and then the wind can shift and pick up as the freezing rain picks up or turns to snow. Imagine the terrible wind load and strain on the supports as the antenna whips in the wind, pushed all the more by the greater wind loading due to the coating of ice. When the design limits are reached, the antenna or its supporting structure will fail.

What can you do about ice and wind? My feeling is that moving to someplace with a better climate might be the only sure-fire answer. Some places are more prone to ice storms than others, though, and about all you can do is build your wire antennas to withstand greater loads by using compression-style insulators instead of the "dog bone" style. Compression insulators are much less likely to break because more pull on the wires actually compresses the insulators instead of pulling them apart. Better quality wire can help, too, as can good, heavy-duty hardware at all supporting points. Antenna towers that telescope down during high wind conditions can help protect your antenna investment. At least the antenna will be closer to the ground where the wind may be less, and the entire structure presents less of a wind load when telescoped in the down position.

My wire antennas are not that great. One is a commercial Windom about 125 feet long and the other is an end-fed wire, also about 125 feet. Neither one was mounted with heavy-duty hardware, so if they come down in an ice storm with lots of wind, I wouldn't be surprised. What I am doing is sort of playing the odds, since we don't get those conditions together too often here. My Butternut vertical can pretty much take care of itself because it has almost no horizontal surfaces to collect heavy ice. Flexing in the wind just breaks the ice off and it falls harmlessly to the ground around the base. It is really the horizontal surfaces that you have to protect the most from icing. How much is an airline ticket to Florida? Can't afford that? Try getting some compression insulators - they're a lot cheaper.

Patrick Tice, WA0TDA
Handiham System Manager
wa0tda@arrl.net

Wednesday, March 16, 2011

Handiham World for 16 March 2011

Welcome to Handiham World!

Fukushima nuclear plant prior to earthquake, photo courtesy Wikimedia Commons, licensed under GNU.
Photo: Fukushima nuclear plant near Okuma, Japan before the earthquake and tsunami damage. View shows three cooling towers and one of the reactor buildings with ocean and docks to the right of the picture. Image courtesy Wikimedia Commons, from Wikipedia.

The unfolding tragedy in Japan is front and center in our minds this week. I talked with long-time Handiham volunteer Mark Booth, WA0PYN, earlier this week. He had already handled a couple pieces of health & welfare traffic on 20 meters. ARRL is keeping us up to date on its website, so there is no need to go into detail on events that are already being covered at ARRL.org. Rick Palm K1CE, edits the ARRL ARES E-Letter, which refers amateurs to the ARRL.org story "Japan Asks Radio Amateurs to Keep Frequencies Clear As Country Goes into Recovery Mode after Devastating Earthquake". Information about the operations of the JARL HQ station JA1RL and the list of frequencies are found in that ARRL story. We suggest checking ARRL.org periodically for updates.

Some of our members who check into the daily Handiham net have been asking about Shinji, JA7QHM. I have not heard from him and would appreciate any news if anyone else has contacted him recently. Shinji had regularly checked into the Handiham net, but usually in the summertime when Daylight Saving Time is in effect. This makes the timing a bit easier as he doesn't have to stay up so late. I called him on Skype this morning but there was no answer or voicemail message.

As long as I mentioned DST, I might as well remind everyone that the Handiham net stays true to local time. That means the difference between GMT and Minnesota time becomes 5 hours instead of 6. Since we are west of Greenwich about 1/4 of the way around the globe, GMT is always ahead of us. By the time the Handiham net is getting underway in the late morning in Minnesota, it is already late afternoon in Europe. You might think that it would be easier to stick to UTC, or "Coordinated Universal Time", which is the same as what us older guys refer to as "GMT". We tried that years ago, but the confusion about the net made the "tech support" just about impossible. We gave up on that and returned to keeping the net at local time, which means that it shifts one hour relative to UTC (GMT).

Since today is Wednesday, that means we also have the evening net to think about. We meet once again at 19:30 hours Minnesota time (7:30 PM), which is at 00:30 hours GMT, or just after midnight in Universal Time. If you are in Europe, that makes it slightly easier to check in because you don't have to stay up quite as late.

All of this reminds me that we are such a worldwide system, email remains the tried and true way to touch base for many of us. It's a great way to work around all of these time shifting issues. I'm not sure if all of you knew about it, but my son Will, KC0LJL, spent a semester studying in Japan last year and made many friends there. We also had quite a parade of Japanese exchange students though our home over the past year, so obviously we have an interest in keeping track of how they are doing. Facebook has been a great contact tool and, as ARRL points out, internet connectivity has remained good in most of Japan. We are considering a Handiham group under the wing of Courage Center's Facebook page. Although I prefer email to using Facebook for individual messages, I know that this new media is more and more in the news these days and sometimes general interest stories in ham radio might be better covered in a Facebook forum. ARRL is on Facebook, as are many ARRL and Handiham members. It's something to think about for sure!

Finally, the Japanese situation includes a nuclear reactor emergency. This is bound to create a new awareness of communications preparedness related to ARES training. Some time back, a local ARES group here trained with other emergency services personnel in a mock nuclear plant scenario. It will be interesting to see what new procedures might come about as we learn more from following the news and response to the Fukushima nuclear plant damage. Communications technology and procedures are always changing to meet new and different challenges.

ARRL members who wish to receive the ARRL ARES E-Letter may manage their mailing lists directly from the member section of ARRL.org.

Patrick Tice, WA0TDA
Handiham System Manager
wa0tda@arrl.net

ADA Changes in Effect

Cartoon familiy holding hands, one family member using wheelchair.

Revised regulations implementing the Americans with Disabilities Act (ADA) took effect yesterday, March 15, 2011, the Department of Justice announced. The revised rules are the department's first major revision of its guidance on accessibility in 20 years.

The regulations apply to the activities of more than 80,000 units of state and local government and more than seven million places of public accommodation, including stores, restaurants, shopping malls, libraries, museums, sporting arenas, movie theaters, doctors' and dentists' offices, hotels, jails and prisons, polling places, and emergency preparedness shelters. The rules were signed by Attorney General Eric Holder on July 23, 2010, and the official text was published in the Federal Register on September 15, 2010.

Wednesday, March 09, 2011

Handiham World for 9 March 2011

Welcome to Handiham World!

Pat, WA0TDA in ham shack, holding hand microphone.

A couple of months ago my local radio club decided to bring back their monthly newsletter. The newsletter had been absent as a club communications tool for a few years, although there was a well-maintained website with frequent updates by multiple contributors. At least part of the reason the newsletter is returning to our club is that I suggested at one of the club meetings that it do so and that I would help to edit the new publication. So far, so good! There are two of us sharing editorial duties and several club members have stepped up to the plate and contributed columns and stories so that no one person is responsible for doing all of the work each month. Working together as a team allows the newsletter crew to turn out a good product that is an asset to the club.

But why is a newsletter still important in this age of constantly-available information that bombards us from every direction?

It's hard to put one's finger on exactly why people prefer one news and information source over another one. The obvious preference for a traditional means of reading the club news, a print newsletter format that has been successful for years, perhaps decades, is one consideration. If your club is anything like mine, there are going to be several club members who do not have computers and who feel left out without a monthly newsletter that they can actually hold in their hands and perhaps even mark or take notes on with a pencil. Although individual stories from a club website can be printed up for members who do not use computers, it really isn't even close to the same thing as an official club newsletter that pulls together all of the information in one single publication. Then there will be the other club members who have and use computers but who still prefer the traditional print format. Even some people with advanced technical skills find a print newsletter more compelling and relaxing to read, especially if they sit in front of a computer screen all day long at the workplace. A print newsletter can also be passed on to another family member or a friend. A physical newsletter is not quite as easy to forget about as a web link that someone might give to you. A print newsletter can be read without any device or Internet access.

The last time I checked my calendar, it was 2011. With our feet firmly planted in the 21st century, even a print newsletter for your radio club must have a digital online edition. The reasons for this are pretty obvious; there will be people who prefer to read everything online. It is important that the club serve the newsletter up for these people on the website because doing so will save printing and mailing costs, probably for the majority of club members. In fact, our club seldom mails anything out these days, much less newsletters. It makes more sense to produce the newsletter in PDF, place it on the website as a download, and allow club members who want to read a print newsletter to go ahead and download and print the publication for themselves and for their friends. Several printed copies will be available to distribute at club meetings to members without computers. A few newsletters will be available to mail out to club members who are out of State for the winter or who are unable to get to a club meeting because of health or transportation issues. Furthermore, the PDF version necessarily contains embedded text that can be read by blind members who use screen reading technology.

So the club newsletter of 2011 is different from the club newsletter of 1991 or 2001. The differences are obvious even to club members who read the print edition. The layout and color photos wouldn't be possible without modern software like Microsoft Publisher. The content itself is available 24/7 on the club website for club members to explore months or years after it was first published. Articles are searchable by computer. Content is accessible to blind computer users. Before all of this new technology came along, club newsletters were pretty basic-looking monochrome publications that were sometimes done on mimeograph machines. There is no doubt that the 21st century amateur radio club newsletter can be a pretty impressive looking publication!

However, the newsletter still serves the same basic purpose of communicating to club members in a way that it always has. Monthly meeting announcements and notes, things that are happening in the lives of radio club members, amateur radio news of broader importance to everyone, club calendars, regular columns by club members or officers, minutes from the previous month's meeting, and all of the other timely news collected in a single place each month make up the traditional content of a typical monthly issue. The newsletter is fundamentally different from a website in that it represents information that has been collected, edited, arranged, and presented in a very specific way at a specific point in time by editors. The monthly publication, once posted on the website, is the official newsletter for that month. This may be seen as hopelessly outdated by some people who cannot understand why anyone would want to look at a news source that isn't constantly updated, but on the other hand may be seen as a huge asset by others who don't care to devote the time and attention to a club website where information overload can lead to missing important stories that might not be near the top of the pile of information.

One of the problems club websites have is simply that they must compete with hundreds of other websites for our attention every day every month every year every hour. Although at the time dropping a regular monthly newsletter seemed like a good idea, having the newsletter as a single point of collected information each month now seems like it is a little bit too important to give up just yet. That is the reason that I volunteered to help edit my club's newsletter. Yes, it is another thing to do in my already busy life, but I know that I have the ability and desire to help my radio club in this activity and I realize that making a radio club a successful endeavor is something that requires all of us to roll up our sleeves and pitch in. I would like you to think about how you are helping your local radio club to be the best possible organization it can be. You may not be able or interested in editing a club newsletter, but you may have time to write an article or a monthly column about one of your amateur radio interests. You may have time to write an occasional column, perhaps promoting Handihams or the Handiham nets to your local club via the club newsletter or website. If you are simply not a writer, there are still plenty of other opportunities to participate in your club's activities. Although showing up for meetings is important, your radio club will be better off and you will have more fun if you sometimes raise your hand to volunteer to help put together the club's field day activities or the club picnic. Monthly meetings are generally divided into the business part of the meeting and some kind of club program. If you have a special interest in amateur radio and would like to put on a program for your club, I'd be willing to bet just about anything that you would be welcomed with open arms. Most clubs are eager to find presenters for the club program, instructors for their licensing classes, and volunteer examiners for their VE teams.

I guess my point is that you can't be afraid to step forward and do something for your local radio club, whether it is working on the newsletter or some other club project or on the air activity like the net or the repeater. Every active organization will have volunteer opportunities. I hope you will step up to the plate. You will have more fun and your club will be the better for it!

Patrick Tice, WA0TDA
Handiham System Manager
wa0tda@arrl.net

FCC issues three accessibility-related NPRMs - Handiham members might want to comment!

FCC round logo

Washington, D.C. – As part of its ongoing efforts to implement the “Twenty-First Century Communications and Video Accessibility Act of 2010” (CVAA), the Federal Communications Commission issued three Notices of Proposed Rulemaking (NPRMs). The CVAA is considered the most significant piece of accessibility legislation since the passage of the Americans with Disabilities Act in 1990.

Wednesday, March 02, 2011

Handiham World for 2 March 2011

Welcome to Handiham World!

Lyle, K0LR, and I have made really good progress with the W0ZSW remote base beta test, so this afternoon the station will go off the air as I prepare to transport it to its new location at Camp Courage. We still have a few problems to iron out, so the old TS-570SAT will probably have to go back on the air for a while.

When I get out to camp tomorrow, I will be working to get the network problem repaired. After that, we can get the TS-570 back on line and into service for our members. Now, you must be wondering what issues still remain with the TS-480HX setup, right?

Well, there are several:

The TS-480HX is, of course, the 200 Watt version of the popular TS-480 series by Kenwood. Most users opt for the SAT version, which runs 100 Watts. We figured that the 200 Watt version would add some extra punch to the signal, and it would be especially useful in the summertime when interference levels from summer thunderstorms around the country are higher. The problem is that the W4MQ rig control software keeps dropping the power level back to 100 Watts. Of course this is not a deal-killer, since the 3 dB drop in signal strength is not going to be a problem most of the time. I have posted the issue on the N2JEU remote base development website in hopes of getting some help with this issue.

The receiver audio equalization always defaults to "high boost", which makes the sound a little on the screechy side for my taste. Those with hearing deficits may prefer the high boost, though, so this is not necessary a bad thing. To get a mellower sound you have to change the receiver equalization to "normal" after logging in. When you log out, it returns to the default "high boost" setting. We would prefer that it worked the other way around, where the normal audio setting would be the default.

The radio is supposed to turn off shortly after the control software on the host machine is disconnected from the W4MQ interface by the control operator's log off. Instead, the radio may indeed turn off, but it always turns itself back on after about a minute even though no one is using it, whether through the W4MQ software or to listen to the receiver via Echolink. This is a bit of a headache, because we would rather the radio were off when not being used. Left to its own devices, the radio will run 24/7. This problem seems unique to our new beta test setup since we don't have any problem with the W0EQO station or the old W0ZSW station using the TS-570SAT.

Those are the main concerns with the new system. As you can tell, since the radio and computer are actually working quite well otherwise, we could put the station on the air any time. Still, I'd rather try to get things working just a little better and have the system the way it should be as we "go live" so to speak.

If I am unsuccessful getting the network problem resolved, W0ZSW will be offline for a while but hopefully the Echolink receive function will still be enabled through a proxy server.

I provide a short overview video of the W0ZSW remote base beta test on YouTube. Look for WA0TDA's channel.

W0ZSW beta test setup at WA0TDA QTH

Photo: The W0ZSW beta station as featured on YouTube.

Patrick Tice, WA0TDA
Handiham System Manager
wa0tda@arrl.net