Grounding for lightning safety
Gary Coffman, KE4ZV
Reasons for grounding a station
You commonly hear three:
1. to improve RF performance
eliminate stray RF in the shack
3. to improve electrical safety.
But in most circumstances only the last has merit. (Let's see where the truth is grounded.--AF6S)
1. Improve RF performance
The proposition that a better ground improves RF performance is false except with
antennas that must work against ground. Even then, the ground should be at the antenna feed point, not at the transmitter. (Of course the transmitter can be at the feed point of a long wire antenna.)
A balanced antenna (dipole, Yagi, or
quad) operates independently of ground. It even works in free space--no
ground connection at ail. The same holds for a vertical with above-ground radials or a counterpoise.
But many verticals, long wires, and other symmetric antennas do require grounds--again, best at the feed point.
2. to eliminate RF in the shack People often give this as a reason for an RF connection to Earth. But, like taking aspirin for a brain tumor, a shack ground may suppress the symptoms but do nothing for the underlying problem--which may be a faulty station layout or design. RF in the shack can result from equipment with poor shielding, unbalanced feeder currents, or "daisy chained" station interconnections that create "ground loops."
Grounding one or more cabinets may even increase the problem. (Though connecting all the cabinets to a common point, "star wise," usually helps - AF6S.)
be at the feedpoint of a longwire ante A balanced antenna (dipole, Yagi, quad) operates independently
Contesting: a primer for beginners
Lee Zalaznik, KI60Y
Contesting can be an adventure-packed weekend of making as many contacts as you could in a whole year! Contesting has many rewards! For most of us winning is not everything but making that better score than last year or trying out a new mode is the thrill. Most contests are faster paced than others and also have different rules or requirements. If you are getting into contesting, give some of the smaller SSB and CW contest put on by 10-10 International a try. With the propagation improving, these sets of contests will be a good way to start contesting. They take place four times a year. There are two SSB contests in the winter and summer and two CW contests in the spring and fall. These contests will give the Amateur Radio operator an ample number of contacts - a good score and a lot of fun. Check this out at www.tenten.org.
The next sets of contests are for the more seasoned operator. The IARU contest is a "work anyone for points" contest with a nice multiplier structure. Most of the rest of the major HF phone contests are fast-paced such as the ARRLDXSSB and the ARRL 55 SSB contests. The CVV contests are a notch up in speed but can be conquered with some practice such as the CQWW DX contests.
The state QSO parties can be fun! There is always room for another station on the air from your state.
See Contesting page 7
Maybe it’s a little early in the year but I thought I would let you know anyway.
Starting in January 2001, or maybe before CQ de WA2LQO will publish a happy birthday column for its members.
The column will not be over done. Just happy birthday wishes for our members in the month they were born.
If you do not whish to have your name and call appear in such a column let me know. If we omit your name and call and you want your name to appear, let me know.
The Editor, KA2FEA
CQ de WA2LQO
VOL. 74, NO. 11
DAVE ANDERSON, KA2FEA
PAT MASTERSON, KE2LJ
CQ de WA2LQO is published monthly by the Grumman Amateur Radio Club for its members and friends. Send articles and amateur equipment advertisements to:
Phone (631) 361-8910
If you want to submit articles or amateur equipment ads via e-mail do the following:
1. For submission direct to editor call him at above number to set up a transfer.
2. For e-mail transfer:
GRUMMAN AMATEUR RADIO CLUB OFFICERS FOR 2000
President Pat Masterson KE2LJ B38-111 218-6746
Vice President Gordon Sammis KB2UB C63-005 575-1846
Secretary Peter Rapelje N2PYV Retiree 676-0694
Treasurer Ted Placek KD2UB
1Yr Board Member Zack Zilavy WB2PUE 667-4628
1YrBoard Member Dave Ledo AB2EF
1Yr Board Member Martin Miller NN2C Retiree 423-8153
2Yr Board Member Bill Scheibel N2NFI 924-0126
2Yr Board Member Dan Manfre WA2NDP
Trustee WA2LQO Ray Schubnel W2DKM C31-005 575-5036
STANDING COMMITTEE CHAIRMEN
Meeting Programs Contact a Board Member
FCC Exam Coord. Bob Wexelbaum W2ILP 499-2214
"Is it time yet?" People associated with GARC are beginning to ask me this question more than ever. In the face of the declining membership of GARC, and all of Ham Radio everywhere, can we keep the Club alive Or is it time to let it slip away forever? We also have the problem of lack of support from most of the Company. While there are people in some areas that still support us, our key helpers from the past are all gone. Those friends of the Club who are left, are somewhat ineffective in helping us. So, we need to decide what to do. But, we can put off that painful decision for a while longer, and I'll tell you why. It's because we still have a few tricks up our sleeve.
Last week I
was taking my wife for her flu shot, and we were driving east on 25A out of
So, I wondered what Dave would do if he were here now. And I think I know the answer. Dave would stop talking to the people who only wanted to keep discussing things. He would go out and make something happen. This isn't an operating style that's appropriate for everybody, and maybe not me. But, we are in need of some desperate measures now, and a different mode may be required. So, let’s try to find a way of replacing all this talk with some real action. We need to come up with some plan to keep this Club going, even as the Company fades away. Give it some thought, and hopefully we can get something going real soon.
As you know,
I was extremely disappointed with the response I got from Bethpage Water to my
request for antenna space on their new water tower. Yes, the tower that
Northrop Grumman gave them $4 million to build! They were very discourteous to
me with their terse reply. I had asked for an informal meeting in which I could
discuss the issues, but I was sent a
curt letter by their lawyer dismissing us with no chance to discuss things. So,
last week I succeeded in having a phone conversation with a Town official. This gentleman was not only aware of Skywarn,
and RACES, but was unhappy to hear of
the manner with which we were treated. He asked me to collect copies of the
letters between myself and the Water people, and forward them to him for
analysis. Of course, he couldn't make any promises, but he will try to help if
he can. So, we are still moving forward in our quest to keep the
But, I am having less luck getting our trailer moved to a decent site, and the tower erected. The Company has backed away from a plan to relocate us to a site near Plt 14. As always, it's a cost issue. Initially it was about the price for having aircraft warning lights on the tower. To deal with that, I contacted a Ham friend in the FAA, and he had me send some maps and paperwork to him. Hopefully, we will get an official FAA ruling on the necessity of lights. And I'll have lots more to tell you next time. Well, is it time yet? I don't think so! But ask me again in 6 months. See you at the meeting!
original source of this article is unknown, but it was downloaded from the
internet and provided by NY2V.A rather inhibited engineer finally splurged on a
luxury cruise to the
Outside of beautiful scenery, a spring-fed pool, bananas and coconuts, there was little else. He lost all hope and for hours on end, sat under same palm tree. One day, after several months had passed, a gorgeous woman in a small rowboat appeared.
“I’m from the other side of the island," she said. "Were you on the cruise ship, too?" "Yes, I was, "he answered. "But where did you get that rowboat?"
"Well, I whittled the oars from gum tree branches, wove the reinforced gunnel from palm branches, and made the keel and stern from a Eucalyptus tree."
"But, what did you use for tools7" asked the man.
"There was a very. unusual strata of alluvial rock exposed on the south side of' the island. I discovered that if I fired it to a certain temperature in my kiln, it melted into forgeable ductile iron. Anyhow, that's how I got the tools. But, enough of that," she said. "Where have you been living all this time? I don't see any shelter."
"To be honest, I've just been sleeping on the beach," he said. "Would you like to come to my place?" the woman asked. The engineer nodded dumbly.
She expertly rowed them around to her side of the island, and tied up the boat with a handsome strand of hand woven hemp topped with a neat back splice. They walked up a winding stone walk she had laid and around a Palm tree. There stood an exquisite bungalow painted in blue and white.
"It's not much, but I call it home." Inside, she said, "Sit down please; would you like to have a drink?" "No, thanks," said the man. "One more coconut juice and I'll throw up!" "It won't be coconut juice," the woman replied. "I have a crude still out back, so we can have authentic Pina Coladas." Trying to hide his amazement, the man accepted the drink, and they sat down on her couch to talk. After they had exchanged stories, the woman asked, "Tell me, have you always had a beard?" "No," the man replied, "I was clean shaven all of my life until I ended up on this island. Well if you'd like to shave, there's a razor upstairs in the bathroom cabinet.'' The man, no longer questioning anything, went upstairs to the bathroom and shaved with an intricate bone-and-shell device honed razor sharp.
Next he showered -- not even attempting to fathom a guess as to how she managed to get warm water into the bathroom and went back downstairs. He couldn't help but admire the masterfully carved banister as he walked. "You look great," said the woman. "I think I’ll go up and slip into something more comfortable." As she did, the man continued to sip his Pina Colada. After a short time, the woman, smelling faintly of gardenias, returned wearing a revealing gown fashioned out of' pounded palm fronds.
"Tell me," she asked, "we've both been out here for a very long time with no companionship. You know what I mean. Haven't you been lonely, too...isn't there something that you really, really miss? Something that all men and woman need? Something that would be really nice to have right now!” "Yes there is!" the man replied, shucking off his shyness. "There is something I've wanted to do for so long. But on this island all alone it was just...well, it was impossible. "Well, it's not impossible, any more," the woman said. The man, practically panting in excitement, said breathlessly: "You mean... you actually figured out some way we can CHECK OUR PACKET MAIL HERE!!??!!”
Grounding from page 1
Sometimes connecting everything to a good RF ground reduces stray RF at one frequency, but makes it worse at another.
3. for electrical safety
This is the best reason for a grounding ! system. An effective grounding system s can eliminate two different hazards.
The second reason for effective grounding is lightning safety--a difficult problem one should approach with care, because a single mistake can be so costly.
Lightning surges of 8,000 amperes are common, and occasional "super bolts" reach 200,000 amperes. These discharges last only microseconds, so their average power is low. In one sense, fast current rise time, lightning is RF. The fast rise-times mean a lightning strike can develop kilovolts of potential difference across the inductance of even a short down lead. If these potentials develop between equipment cabinets, a strike may destroy you and the equipment's sensitive components.
Single-point grounding Single-point grounding is a simple concept that can be subtle in execution. All connections to earth must go directly to a common point, and all connections from equipment that needs a ground termination must run to that ground point and no other. Daisy chaining grounds isn't allowed.
Also, every connection to the single point must be straight, and direct. "Ground busses" are a serious no-no, though you'll find them touted in Amateur literature. Busses form instant ground loops. At the currents and rise times in a lightning discharge, they can allow thousands of volts to develop between equipment cabinets. The idea of the single-point ground is that it forces everything to the same potential, that of the single point. And zero lightning-caused potential difference means zero current flowing through the equipment. Of course the single-point "ground" itself will not stay at zero volts during a strike. But that's okay; it's the lightning-caused current and potential differences that concern us.
Pondering the many "ground" interconnections in your station, you may conclude that a true single-point ground is impossible. That's where the concept of the "ground window" comes in. The ground window is a small metal plate through which every cable that enters or leaves your station must pass. You bond the wire or shield in each cable that is supposed to be at ground potential to the plate where it passes through.
Also, every conductor that is not a "ground" connects to an appropriate suppression device whose ground you also bond to the plate. Then you bond the plate itself to the single-point ground via a heavy, wide metal strap or braid.
The ground window shorts out any large potential differences that otherwise might develop between cables connected to various cabinets in your shack. Note that EVERY cable on its way in or out of the shack must pass through the ground window--including power, telephone, network cables, antenna feeders, and rotator wires. Allowing just one cable to bypass the ground window ruins the protection. You can't run an extension cord to a power outlet that doesn't pass through the ground window.
After you've taken the pains to install a truly protective grounding system, you'll find it makes an excellent RF grounding system too. And you'll be able to stay on the air during the worst thunderstorms, operating your station without the risk of damage or injury.
Proper grounding isn't magic. It's a welt-understood science more Amateurs should learn about and apply.
From Nov. ’95 Old Virginia Hams ARC (
The meeting was called to order by Pat at 6:35 PM. All present introduced themselves.
TREASURER'S REPORT -
Ted was absent so we did not have a treasurers report.
REPEATER REPORT –
Gordon reported that a new repeater-coordinating group was formed in January, 2000 by the name of METROCOR. They are taking the place of TSARC. We will wait a few months to see if they stay in business before registering with them.
Both of our repeaters are working. Still trying to get in touch with Bill, N2NFI to go to site.
NET REPORT –
The Sunday 40 Meter Net was great. Today's 20 Meter Net had 3 check-ins. The Thursday 2 Meter Net has had poor attendance.
VE REPORT –
Bob reported that there were 3 VE's present and 1 applicant. He failed the Extra written test.
WAG REPORT –
HOUSE REPORT –
The Recreation Department says everything is on hold pertaining to the move of our trailer and tower to the Plant 14 area. Pat has contacted a friend from the FAA to inquire about the need for a light on our tower because it is near the Cablevision helipad. He put Pat in contact with another individual in the FAA who said we must fill out a form and submit it. He intimated that the FAA does not require lights on towers near private aviation facilities.
Two new members were voted in:
Herman J Hugo, WA2MJA, Advanced class - Full Member
Barry Kaufman, WA2B, Extra class - Sustaining Member
Bob, W2FPF was selected to be Election Chairman.
Marty, NN2C was absent, so we did not have a program.
GRUMMAN AMATEUR RADIO CLUB
MINUTES OF GENERAL MEETING 10/18/00
By Pete, N2PYV
Forty Meters: 7.289 at 7:30 AM EST Sundays.
20 meters: 14.275 at
12 noon Wednesdays.
Two Meters: 146.745 at 8:30 PM EST Thursdays.
145.33 at 8:45 PM Thursdays
145.33 at 9:00 PM EST
For information on new VE Exams see write up by Bob, W2ILP in February newsletter, page 2.
General Meetings of the GARC are held on the third Wednesday of each month, at Melville, at 6:30 PM. All who are interested in Amateur Radio are invited to attend. Board meetings are held eight days before the General Meeting and GARC members are invited to attend, but please call Pat Masterson, KE2LJ, at 218-6746 to confirm place and time of meeting
Directions and a map for getting to the Melville meeting site are available on the Club Web site, www.qsl.net/wa2lqo.
Contesting from page 2
The latest equipment and very large antennas are not a requirement to participate in contests, but a well maintained station with a working transceiver or separate receiver and transmitter are required. I have had equipment failures more than once during a contest. Check out the transmitter and receiver before the contests. Also antennas and feed-lines can get lossy with age. Upgrade or replace before the contests. Make contacts before the contests to get back in the groove of operating! Computers have become a fact of life for the Amateur Radio operator. If you have a computer, use it! It can make life easier! Load, setup and learn to use your favorite logging software. They all do a good job. Station layout is important. Think about how the computer keyboard and the rig are set up and within easy reach.
Techniques and operating skills are all part of the learning process during a contest. There are two techniques, search and pounce and calling CQ.
Search and pounce is going up and down the band and answering stations calling CQ and making contacts. This is a good technique to get the multiplier numbers up and work the rare DX. This may be the only way for low power or QRP stations to make contacts.
Calling CQ is staying on a single frequency asking stations for contacts. High power stations can benefit from this technique. I have found that for a low power station sometimes calling CQ can be a
blessing or a curse! Stations will not hear me and move on to my frequency and start calling CQ- I know that it is time to change techniques, bands or modes. To be productive use a combination of both of these techniques.
If the contest rules permit, which most do, change bands and rework the stations on another band or mode! This will not apply to single band contests such as the 10-10 contest, the ARRL l0-meter or 160-meter contests. Try to work the highest band possible! Follow the sun - early mornings use 20 or 15 Meters. Late mornings and early afternoons use 15 and 10 Meters. Early evenings use 15 and 10 Meters. Late evenings use 15 and 20 Meters and then go down to 40 or 80 Meters.
Some bands may not open up, but keep checking. I have used a logging program to check which bands I have not worked many stations on, and near the end of the contest I concentrate on those bands.
For the contests I work I send in a score. I clear my schedule for that weekend and work as many hours as possible. This may not be the case for others but in several hours you can still have tan. To maximize your rate, I would recommend Friday evenings, Saturday mornings or Saturday evenings picking the bands that seem open given the propagation.
Contesting can seem like a solo endeavor. Most contests have a club entry. Check it out! With some publicity you can get your local club members interested.
Members can operate the contest and send in their logs along with the name of their club for a club score. Check out the rules for club scores. Some contests require a list of eligible members. I did this with the California QSO Party and
the Livermore Amateur Radio club.
About six members joined me in operating and sending in their scores.
Sending in your score is a personal choice. All contest sponsors want to have all the people who operate send in their score. Well, go ahead and send in your score. At least you'll find your call sign in print.
Check out your favorite contest column for the latest up-coming contests and take the plunge!
(from the march, 2000 issue of WorldRadio, Rick McCusker, WF6O ed.)
By Frank Fallon, N2FF ARRL
April 15. 2000
marked an important milestone for Amateur Radio in thc
Many of the new upgraded hams will now be using the HF bands for the first time, and it appears there will be a lot of them from reports of crowds at recent VE sessions nationwide. They will be operating both phone and CW, and some of them won't know what life is like on HF. They may not realize that one doesn't call CQ on HF by tuning to a quiet spot and announcing that they're "Listening on frequency." They won't know much, if anything, about band plans, about nets, about working "up", or a host of other things. They will need help, just as badly as you and I needed help when we first went on HF. They will need to learn things that have never been part of any FCC test. They will need guidance, not hostility and transferred anger from those unhappy with the new FCC license structure. Please, oh please, be generous with your help! Be tolerant of their mistakes and be friendly and tactful when you offer suggestions for improvement. Please put out the welcome mat for them. Let them know also when they've done something right, not only when they've done something wrong. We certainly don’t want a bunch of old grouches turning them away from ham radio! It's going to be our task to Elmer them into Amateur Radio. Let's all provide them with a warm ham welcome.