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The EARS WA4IWLetter



In ham radio we know that we must operate under a set of rules and regulations, e.g., you're either inside the band or you're outside the band. A digital circuit is either on or off. We hook up our rigs so that the positive 12 volts goes to the correct terminal--otherwise the rig has to be sent in for repair. Antennas have to be of a calculated or designed size or they don't work. In other words, we amateurs are dependent upon facts--not "fancy".

In my former career as a civil/sanitary engineer, there was no question but that everything had to be designed according to formulae and constructed according to design. Otherwise, the finished project didn't work. Plain old facts--not "feelings".

All of us learn, one way or another, that regardless of our dreams and wishes, we can spend no more than we earn. Now that is a fact!

It seems, however, that many of our country-folk are now overlooking facts in favor of "feelings" or "emotions". I witnessed this in August when I served as an alternate juror in Criminal Court in Sarasota County. As an alternate, I heard all the testimony however I did not sit in the jury deliberations.

The case involved a guy beating up his live-in gal friend (of some 7 - 8 years); a charge of battery. Two Deputies provided verbal testimony and photographic evidence. The defendant testified that the blood on the floor was from the victim cutting her fingers on a broken light bulb and the gash on her leg was from shaving. The victim, who had eluded several attempts to be served with a summons to appear for the prosecution, showed up to testify in defence of the defendant. Conflicting testimony was evident.

The judge's charge to the jury was that they consider only the facts presented to them and that the verdict had to be unanimous. At that time I was dismissed, so I meandered out to the hallway to pass the time with Deputies and State Attorneys. The deputies agreed with my assessment that "Those two sure deserve each other". I then learned they both had long rap sheets and he had been in court before on the same charge. Nice folks!

When I called the State Attorney's Office the Tuesday after Labor Day, I was truly shocked to learn that my fellow jurors had found this guy "not guilty". How could they? Didn't they heed the facts? I commented to the attorney that "feelings overruled facts". Her attitude was philosophical--like, "maybe next time".

On 07 November all registered voters will have the opportunity to serve as jurors in determining the course of our country. As radio amateurs, dependent on facts, we might recall the words of Thomas Jefferson, that "No government can continue good but under the control of the people and...their minds are to be informed by education what is right and what wrong; to be encouraged in habits of virtue and to be deterred from those of vice....These are the inculcations necessary to render the people a sure basis for the structure and order of government."

73 de Jack, W4JS


The next EARS meeting will be held at 7:30 PM, 20 October in Room 400, Friendship Hall of the Englewood United Methodist Church, 700 East Dearborn St. Following the business meeting, the program will be the frequently advertised but not yet seen video of a "1935 Tour of ARRL Headquarters".


The 2000 EARS Christmas Dinner will be held on Monday, 11 December at the Hills Country Club, Rotonda Circle in Rotonda--the same venue as last year. Once again, Micki Maren has been kind enough to initiate arrangements with the club management. A selection from three entrees will be available, and the price should be about the same as last year. Mark 11 December on your calendar now.


On 12 September the Lambda ARC, a Philadelphia-based radio club for homosexuals, wrote the ARRL requesting the "ARRL officially and publicly distance the League from the policy of Boy Scouts of America to dismiss and exclude gay scouts and scoutmasters." (Some years ago the ARRL caved in when LARC threatened a lawsuit over ARRL's refusal to run their classified ad. Now a "Rainbow ARC" ad is also to be found in QST.) (From 01 October 2000 W5YI Report)

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Minutes of the Meeting

September 15, 2000

President Jack Sproat-W4JS called the meeting to order at 7:30 pm with the Pledge of Allegiance to our flag. There were no new members and no guests present. A total of 20 members were present who introduced themselves by call sign and QTH.

There were no additions or deletions to last month's meeting minutes. Art Komarek-WB9VQD made a motion to accept them as published. The motion was seconded by Keith Herve-WL7CKY and passed.

Treasurer Howard White-KD4MMY reported we have $4454.01 in the bank. $114.06 was spent during August on newsletter expenses and name badges. Receipts totaled $28 from an ARRL renewal by Bob Fountain-KI8DS. If you forget to renew your ARRL membership through the club (which nets the club $2) just slip Howard a couple bucks and all will be forgiven. Finally, Howard's motion for acceptance of the Treasurer's Report was seconded by Gabe Meckenberg-K2GQU. The motion passed unanimously.


A "thank you" letter was sent to Karen Parker, Executive Editor of the Gasparilla Gazette, thanking her for that paper's coverage of EARS participation in the International Lighthouse Weekend from Boca Grande Lighthouse. A second "thank you" was sent to the Florida Park Service for their support and cooperation during the lighthouse event. This year 313 contacts were made in 15 countries.

EARS members provided communications support for Englewood's Pioneer Days Parade on Labor Day. On hand: Ron-KE4JWB and Doreene-KF4JCS Snowdon, Ken Anderson-W4JQT, Bruce Robideau-K2OY, JR House-K9HUY, Bob Carstens-KG4IAW, Don Dold-KD9SJ, Vic Emmelkamp-KF4VHX, John Fellin-WB0GUX, Ken Blackshaw-W1NQT and Jack-W4JS.


SUNSHINE - Gene Fowler-KA1GCU reported everyone is healthy again.

TESTING - There will be a session tomorrow.

EOC - Bruce Robideau-K2OY reminded members that RACES drills are scheduled the 9 a.m. the last Thursday of the month at the San Casa Charlotte County Administration building.

The 146.865 MHz K8ONV repeater in Grove City is operational but still needs a new cable to reduce some extraneous noise. The autopatch and speed dial are working, as is the NOAA weather and time functions. To access the weather, bring up the repeater and enter 55011. Upon completion of the weather message, enter 55010 to turn it off. To access the time enter 400. If you experience any problems, contact Bruce-K2OY.

DX - Bruce-K2OY commented on his DXCC status and announced that he had applied to be a Field Checker for the DXCC program.

Local Government Liaison - Jerry Meckenberg-K2JWE has requested a letter from Charlotte County clarifying Ordinance 3976, which may apply to amateur radio towers but is in need of revision. Jerry will keep us updated.

OLD BUSINESS - Vic-KF4VHX reminded all of our opportunity to set up a display of Amateur Radio gear and memorabilia at the englewood-Charlotte County Library during October. Contributions of ideas, suggestions and exhibits will be appreciated. Contact Vic or Frank Maren-W4VV.

No update on the request from the Alzheimer's Society for communications support for their October 14 fund raising walk, due to absence of Frank-W4VV. Those wishing to participate should contact Frank.

NEW BUSINESS - Jack-W4JS mentioned that by this time last year the Christmas Dinner venue had been established. He will contact Miki Maren to see if she can make arrangements for us at the Rotonda Golf and Country Club again this year.

Jack reported that Sunshine Press is closing and that he would check on a new printing establishment.

FROM THE FLOOR - John Kelly-N1KEN reported a special digital symposium would be held in Ft. Meyers on Saturday September 30 at 2 p.m. All facets of digital transmission will be discussed and displayed, i.e., packet, RTTY, satellite, PSK-31, APRS, etc.

The meeting was adjourned at 8:15 p.m..

PROGRAM - Jack-W4JS presented a two-part overhead slide program. First was an explanation on filling out FCC Form 605 for license renewals and address changes; followed by explanation of compliance with the FCC RF exposure rules effective September 01.

Vic Emmelkamp, KF4VHX



The EARS VE Team offers ARRL VEC license exams at 9:30 am the 3rd Saturday of each month at the Chamber of Commerce building, 601 South Indiana Avenue, Englewood. Two-day advance reservation is required--no walk-ins.

Candidates must bring:

(1) Original license and a copy of that license.

(2) Original CSCE's and a copy of each CSCE.

(3) FCC Licensee ID No. or Social Security card.

(4) Two forms of identification.

(5) A check in the amount of $6.65 payable to "ARRL VEC", or cash in the above amount.

For further information and reservation, contact Jack Sproat, W4JS, at 475-1929


The Snowbird Net meets daily at 10 a.m. on 14.278, and at 7:00 p.m. on 7.230. Stop by and say "Hi"!

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The word "balun" is derived by combining the words "balanced" and "unbalanced", referring respectively to the two ends of a dipole and the single center conductor of a coax feed line. When a single wire transmission line is connected to a dipole consisting of two radiating elements, one on each side of the feed point, some sort of matching device is required so that equal RF currents can flow in both sides of the dipole. A balun provides this conversion, dividing the RF currents in the feed line into a set of two balanced RF currents in the antenna, and also inhibiting antenna currents from returning back to the RF source along the outside of the coax shield.

The two most popular baluns are the "current" or Guanella balun (named after its inventor) and the "voltage" or Rhuthroff balun (also named after its inventor).

The first consideration in use of a balun is the transformation ratio--that is, whether the feed line and antenna feed point impedances are the same or multiples of each other. While most dipoles and yagis have a feed point impedance around 50 ohms, where a 1:1 balun would be used, a cubical quad has a feed point impedance of 100 ohms, where a 2:1 ratio would be appropriate.

Next, determine whether a current or voltage balun is most appropriate. If the coax is attached at the center of a resonant dipole where the antenna current is high and the voltage low, then a current balun will be more effective and often easier to match if you are using an antenna tuner. On the other hand, if the antenna is being driven at some harmonic of its characteristic resonance such that the voltage is high and the current low, then a voltage balun is the better choice.

Since high SWR will develop if the antenna is used at a frequency well away from its resonant frequency, high currents and voltages can develop within the balun, causing its failure. A safety factor of current or voltage capacity from 2 to 5 times normal operating conditions is wise.

Sometimes RF currents and voltages will still appear on the outside of the coax feed line. This may occur when the SWR rises to a point that the balun is no longer efficient in suppressing such currents and voltages. Use of "line isolators" or ferrite sleeves made up of ferrite beads slipped over the outside of the coax at or near the RF feed end of the coax should cure this problem.

(From "Choosing the Right Balun for Your Antenna", Alan Pickering, KJ9N, The Experimenter--The Official Technical Newsletter of the ARRL West Central Florida Section, Issue #3, September/October 2000)



(At the 18 August EARS meeting, Local Government Liaison Jerry Meckenberg, K2JWE, reported he had requested a position paper from the Charlotte County Community Planning Department regarding the "Communications Tower" ordinance #98-53 as it applies to amateur radio antenna towers. The following is an excerpt from the response received by Jerry.

Copies of the relative correspondence will be maintained in the EARS files for future reference and use.)

"After review of the 'Communications Tower' Ordinance, #98-53, staff will concur with you that amateur radio antennas and towers are exempt from the Section 3-9-71.1 of the Charlotte County Land Development Code. However, amateur radio antennas and towers are subject to accessory use standards as set forth in section 3-9-62.1, 'Accessory uses, Building and Structures' and Section 3-9-65, 'Air Hazard Zones.' According to 3-9-71.1 {a(b)}, amateur radio antennas and towers are exempt from the provision provided the antenna and tower does not exceed the federal obstruction standard set forth in 14 CFR Part 77.

"Section 3-9-62.1 pertains to land use classification for antennas and towers and the required yard setbacks from property lines. This section classifies antennas and towers as accessory uses and as such both are required to meet the appropriate yard setbacks of the underlying zoning district.

"Section 3-9-65 addresses height limitations in relation to an airport or airstrip. Any antenna or tower within an airport overlay zone must conform to the height limitations of this section.

"Sincerely, Ed Courton, Planner II"


The FCC has information that Joe Keller, W8WW, over in Lake Worth has "...been interfering with communications on 28.425 MHz by deliberately transmitting unreasonably close to that frequency while other licensees or groups were using that frequency", and was given 20 days to respond to the allegations. (Old Joe can be heard almost daily now on 28.422.1, often voicing his negative opinion of the 10-10 members who gather on 28.425 to exchange greetings and numbers.)

The FCC is requiring Lazaro Duarte, KF4WSM, of Miami to retake his Tech + exam prior to 15 October 2000.

Julio Cedeno, N2GRM, of Hollywood, has been warned by the FCC that he must adhere to the Amateur Service identification rules or face enforcement action. He apparently has ignored several notices from Official Observers.

(From 01 and 15 September 2000 W5YI Report)

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-- LEW McCOY, W1ICP, SK --

The same day the polls closed for the 2000 QCWA Election, 31 July 2000, QCWA Past President ('94-'96) Lew McCoy, W1ICP, passed away at the age of 84. He never knew that he had earned a Director's seat on the Board in that election.

McCoy was on the ARRL HQ Staff from 1949 until 1978, where he gained a reputation for his early work to combat TVI and for his articles in QST. He was noted for his ability to explain technical concepts in simple terms. In the early 1950s McCoy put on a "road show" to demonstrate how to beat TVI by using filtering and shielding.

McCoy was well-known for one of his projects, "The Ultimate Transmatch", and antenna tuner described in an article in the July 1970 QST.

He was also an early proponent of the 5 wpm maximum code speed ultimately adapted by the FCC.

(From October 2000 QST)


There's one lucky ultralight pilot out there somewhere. The pilot hit a 150-ft personal TV tower near West Point, IN, after buzzing some of his friends. About 45 ft of the tower was sheared off, and three guys were cut. Authorities haven't nailed the culprit yet but do have some clues, including a shoe, compass, sunglasses and a can of beer dropped on impact. (From Casey Bell, KQ4YI, via the North Jersey DX Reflector, 18 September 2000)


14 Oct Egypt Shrine Temple ARA Hamfest, 4050 Dana Shores Dr., Tampa. TI: 146.940, Info: Jay, K9BSL (727)822-9107

21 Oct Palm Beach Repeater Assn Hamfest, Amara Shrine Temple, 3650 RCA Blvd, Palm Beach Gardens. TI: 147.165, Info: Ken, KD4CTG (561)640-9447

28 Oct Greater Jacksonville Hamfest, Morocco Shrine Auditorium, 3800 St John's Bluff Rd, So. of Beach Rd. TI: 146.76, Info: Deborah, KG4ADZ (904)739-9713

04 Nov Lake ARA Hamfest, East Lake Chamber of Commerce Bldg, 31336 Hwy 437, Sorrento. TI: 147.255, Info: John, W8KCE (352)394-2723

11 Nov Port St. Lucie Hamfest, St. Andrews Lutheran Church, Prima Vista Blvd. TI: 146.955

(September 2000 CyberSKIP Digest; October 2000 QST)



(One of our Canadian members took issue with last month's "President's Message"; taken from a Canadian TV commentator's editorial. Our VE member took the article to be "self-serving", i.e., pro-American, and putting Canada in a negative light. While I cannot read any negative sentiment in the article, I promised that member "equal time" to show when Canadians assisted us 'Mericans.)

"In the latter part of the last century, Canadian firefighters from Ontario went to Chicago, in numbers, to help with the Great Chicago fire. I understand that there is a plaque, in Chicago, commemorating Canada's participation. After 444 days of detention by the Iranians, it was the Canadian Ambassador and his staff who managed to spirit those American embassy employees to freedom on Canadian passports. Ken Taylor, our ambassador was awarded the Congressional Gold Medal for his efforts.

"When Hurricane Andrew hit Holmstead (sic), Canadian troops volunteered to help with some of the reconstruction. When the Mississipi (sic) river basin overspilled a few years ago, nearly 400 Canadians, mainly from Ontario, showed up to fill sandbags and man the dykes. When severe snowstorms have crippled transportation, particularly in the more southern states, snow removal equipment and manpower has been shipped, at Canadian taxpayer's expense, to lend a hand. Finally, we have the recent example, as shown on a recent episode of '60 Minutes', whereby the assistance of Canadian firefighters to halt the spread of forest fires, was sought by the Governor of Montana and given freely by Alberta and Saskatchewan governments."


Dave Colburn, K1YP, of Hudson has been appointed by SM Dave Armbrust, AE4MR, to serve as the West Central Florida Section Emergency Coordinator. (From The ARRL Letter, September 1, 2000)


FOR SALE - The following equipment is available:

Yaesu FT-890 HF Xcvr w/Cushcraft R7000 10 to 80-m Vertical $800

Yaesu FT-2500M 2-m FM w/manual 200

Call Harley Cox, W0CU, at 426-4361

FOR SALE - Two push-up masts; one 30' and one 40'. $5 each, OBO. Call Ken Anderson, W4JQT, at 475-3172.

FOR SALE - Mosley 3-el "Tig Array" Model MP-33 in excellent condx w/CDR rotator. Antenna can handle 1500 watts. Winner takes all for $225, OBO. Call Larry Yacobeli , W4ERN, at 497-4247 or e-mail to w4ern@ juno.com

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Contest/Special Event Times/Dates Bands/Modes QSO With Exchange
FISTS Fall Sprint 1700 GMT 14 October

2100 GMT 14 October

80 - 10 Meters

CW Only

FISTS Members or Anyone, Anywhere Name/State + FISTS No. if Member
VK/ZL Oceania Contest 1000 GMT 14 October

1000 GMT 15 October

80 - 10 Meters

CW Only

Australian, New Zealand and Oceania Stations Only R/S/T + Serial Number
RSGB 21/28 MHz Contest 0700 GMT 22 October

1900 GMT 22 October

15 and 10 Meters

CW Only

United Kingdom Stations Only R/S/T + Serial Number
Asia-Pacific Sprint 0000 GMT 21 October

0200 GMT 21 October

20 and 15 Meters

CW Only

Asia-Pacific Stations Only R/S/T + Serial Number
Worked All Germany Contest 1500 GMT 21 October

1459 GMT 22 October

80 - 10 Meters

SSB and CW

German Stations Only R/S/(T) + Serial Number
JARTS WW RTTY Contest 0000 GMT 21 October

2400 GMT 22 October

80 - 10 Meters


Anyone, Anywhere R/S/T + Age
CQ WW DX Contest 0000 GMT 28 October

2400 GMT 29 October

160 - 10 Meters

SSB Only

DXCC Countries (USA for Zone Multipliers Only) R/S + CQ Zone
Ten-Ten International Fall QSO Party 0000 GMT 28 October

2400 GMT 29 October

10 Meters Only

CW Only

10-X Members or Anyone, Anywhere Name/State and 10-X No.
ARRL Sweepstakes 2100 GMT 04 November

0300 GMT 06 November

160 - 10 Meters

CW Only

USA Only Serial #, Power Class, Yr 1st License, Sect.
Japan International DX Contest 2300 GMT 10 November

2300 GMT 12 November

75 - 10 Meters

SSB Only

Japanese Stations Only R/S + Serial Number
European RTTY DX Contest 0000 GMT 11 November

2359 GMT 12 November

80 - 10 Meters


European Countries Only R/S/T + Serial Number

From October 2000 Worldradio and October 2000 QST.


The CQ WW DX Contest, scheduled for 28-29 October is considered the premier DX operating event of the entire year. This 50-year-old event attracts more participants from more countries than any other contest. At one time the CQWW was considered for inclusion in the Guiness Book of Records as the world's largest sporting event, but the estimated 50,000 or more participants could not be verified to the Guiness standards. CQ receives almost 10,000 actual log entries every year for the Phone and CW weekends of this contest. The CQWW also attracts its share of DXpeditions, and there are often countries that you can work easily during this contest that are virtually devoid of activity at any other time. If you ever want to work DX, the CQWW is the time to do it.

The exchange in this contest is the signal report, typically "5-9", and the CQ Zone of each station. Florida is in CQ Zone 5. The CQWW shown above is for the Phone weekend; the CW is 25-26 November.

There are 40 CQ Zones in total, and a very attractive certificate is available for working all 40 zones. Very few stations have attained the 5-Band WAZ award.


Beginning this month the contest details that were formerly announced in the pages of CQ are only available on CQ's web site. Look for contest rules and schedules at <www.cq-amateur-radio.com>. (Ed note: Only CQ contests are now listed; that will change.) (From "Contesting", John Dorr, K1AR, CQ, October 2000)

-- JOTA - 2000 --

A reminder that the Boy Scout's 2000 Jamboree on the Air takes place 21-22 October. This is a great opportunity to expose Scouts to ham radio. Although nothing is planned locally, perhaps you can get on the air and work some of the Jamboree stations that will be active. Support the Boy Scouts--it's impossible to find a better organization for the youth in any country.


"Government, even in its best state, is but a necessary evil; in its worst state, an intolerable one."--Thomas Paine

"If we make peaceful revolution impossible, we make violent revolution inevitable."--John F. Kennedy

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(Band/GMT for best chance of S5 or better signal)



BEARING 80 40 20 17 15 12 10
East Timor - 4W/K7BV

Vanuatu - YJ0DX

Malawi - 7Q7CE

Burkina Faso - XT???

Mt. Athos - SY2A

Eritrea - E3???

Kingman Reef - KH5K

Micronesia - V63DX

Bhutan - A52??

North Cook Is - ZK1NDK

Vanuatu - YJ0AD, YJ0AU

Kermadec Is - ZL8/F2CW

Cape Verde - D44DX

Now to 17 Oct

Now to 16 Oct

Now to 24 Oct

Now to 15 Oct

Now to Dec

17 Oct - 01 Nov

18 Oct - 01 Nov

25 - 31 October

27 Oct - 03 Nov

28 Oct - 04 Nov

28 Oct - 05 Nov

02 - 15 November

06 - 12 November









































































































Updated 07 October 2000, based on 09 October 2000 QRZ DX, 06 October 2000 The 59(9) DX Report and OPDX Bulletin #478..

Notes: NO = No opening forecast. ??? = Callsign not yet known. Long path bearings and opening times (if any) are underlined.

Solar Flux assumed at 170 and K-Index at 2 for all forecasts.


The Solar Flux averaged 182 during September, with the A-index < 10 for 16 days. The 12-month running smoothed sunspot number for June was 111, the same as for May. Cycle 23's peak was expected between June and September, so it's down hill from here on, folks. A smoothed solar flux value of 176 is forecast for October. Band-by-band forecasts follow:

10/12 Meters: European openings should peak an hour or two before local noontime, while those to Africa should peak in the early afternoon. Far East, Australasia openings are forecast for late afternoon and early evening. Twelve meters will open and close a bit before and after 10 meters.

15/17 Meters: Excellent propagation from shortly after sunrise through the early evening. Fifteen will peak towards a geographical area about an hour or so after the 10-meter peak has occurred to that area. Seventeen meters will close about an hour after fifteen.

20 Meters: Conditions should peak from an hour or two after sunrise and again during the late afternoon and early evening. Under High or Above Normal conditions (typically a k-index of 3 or less), expect 20 meters to be open during most of the night.

40 Meters: Open to Europe during late afternoon hours, peaking about midnight. Signals from a westerly direction will peak just after sunrise.

80 Meters: Peak openings to Europe around midnight and to the west just after sunrise. Signals will be slightly weaker than on 40 meters and openings will be shorter. Forecast for remainder of October: 15-16, 24, 26-27 should be Above Normal; 10, 17-18, 21-22, 25 and 28 should be High Normal.

(From "Propagation", George Jacobs, W3ASK, October 2000 CQ)


One of the major problems in working the Bhutan DXpeditions is the A5 stations have been limited to 100 watts output. However, Charly Harpole, K4VUD, is going to Bhutan in early December and has permission to run 1 kw output on the "three low bands". If only future DXpeditions could get permission to run more power on the higher bands . "Ya sure can't work 'em if ya can't hear em!" (From OPDX Bulletin #479)


Around 2100 GMT (5 pm EDST) 27 September, Dan, 3W1A, was on 28.495 "beaming USA" and giving N6HK as his QSL manager. What with the time being 3 hours before Saigon sunrise, the signal peaking at 300o rather than 348o, the MUF to Saigon at that time being 16.5 Mc, and N6HK disclaiming any knowledge of this guy, it sure was Saigon Slim in action. "Dan" had guts though, as Slim usually only uses CW! "WFWL"


The Swiss team planning to put 3B6RF on this month had to cancel due to elections in Mauritius and concern for security. (So, how "tight" is the American election?)

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(EARS VP Keith Herve, WL7CKY, and John Kelly, N1KEN, are enthusiastic about APRS--as is the WCF "management". This introduction to the APRS mode is from an article by Frank Ingle, KG4CQK, on the QRZ.com Internet site.)

The Automatic Position Reporting System (APRS) was invented by Bob Bruninga, WB4APR, now living up in Glen Burnie, MD. APRS is not just a communications tool like Packet or RTTY, but rather a whole set of tools all designed to work together.

Geographic Information Systems: APRS provides the display of data on a wide variety of maps. Virtually any map that can be displayed on a computer may have APRS data displayed over it. The display may be in two dimensions (position on the earth's surface) or three dimensions (including altitude). Some of the data typically displayed on a map include storms, weather observations, airplanes, vehicles, runners, bicycles, ham stations, homes, fires, etc.

APRS Software: This is the tool which ties all the parts together and sorts incoming data into meaningful tables. The APRS software may be run on virtually any computer which supports MSDOS (2.0 or higher), MS Windows (3.0 or higher), Macintosh, LINUX and Java. APRS programs have also been written for a variety of postage stamp processors, and at least two Kenwood and one Alinco receivers. This software provides for the handling of data such as position reports, status reports, objects, weather reports, storm data, telemetry, bulletins and beacons.

Global Positioning Satellite (GPS) Systems: The GPS allows users to pinpoint their exact location on the surface of the earth (or above it). Typically, a small antenna--about the size of a computer mouse--can provide digital data containing the latitude, longitude and (sometimes) altitude of the device. When these data are input to the APRS system, all users can see the exact location of that device on a map as it moves. For example, a mobile ham station using APRS could have its location constantly reported to an EOC. APRS can also work with LORAN systems used in the maritime environment.

UI Radio Packets: Packet Radio is a system invented by hams to transmit digital data over radio circuits designed for voice. Data to be transmitted are split into small units ("packets"), converted to audio tones (often via FSK) and then transmitted as an audio signal. On the receiving end, the tones are converted back to digital data and assembled into the original stream of data. "UI" refers to Un-numbered Information, which is a specific type of packet that does not require acknowledgement. Radio frequencies most commonly used by APRS include 144.390, 7.085 (Ed note: Right in the DX SSB window!), 10.151 and 18.107 LSB. However, APRS packets may be transmitted over almost any voice channel including police radios, amateur repeater systems, business band, marine band, Citizens Band, cell phones, and even land-lines.

APRS Digipeater Network: In the 2-meter band, APRS stations with as little as 1-watt power can reach stations as far as 400 miles away. This is accomplished by a network of dedicated digital repeaters (digipeaters) which relay the signals. To avoid network saturation, packets are repeated only three times, hence the 400-mile limit.

Trak-Net: For mobile users in remote areas not served by digipeaters, packets may be repeated via orbiting satellites. The mobile station requires a 10-watt output and a 5/8-wave antenna to uplink a signal on 144.900.

APRS-NET: In addition to staying in touch via radio, APRS can take advantage of the Internet to transmit data to stations out of radio range, or to stations not equipped with radio capabilities. By design, APRS data are only transmitted about 400 miles by radio. However, the Internet allows users all over the world to exchange data when desirable. Virtually any computer with APRS software and a modem may receive data from the APRS-Net. (ISP not required!)

ZIP-LAN: For computers not already connected to a network, a very inexpensive serial data network may be set up to provide all users access to APRS data. This would be useful in a Police HQ or EOC where there may be computers that normally work independently but would all need access to APRS data in an emergency.

Weather Station: Inexpensive weather monitoring equipment may be connected to an APRS station to provide a continuous stream of weather observations from that station's location. Parameters such as temperature, wind speed and direction, barometric pressure, rainfall and humidity are often available on a real-time basis.

Aircraft Communications and Reporting System - ACARS: Commercial aircraft use this packet system to stay in touch in the 129 - 131 MHz band. If a TNC is programmed to recognize these packets, they may also be reported by APRS, giving position information on all participating aircraft within 200 miles.

In summary, there is a lot to APRS--more than can be learned in one sitting. As "a picture is worth a thousand words", one could learn a lot more about APRS by seeing it than by reading about it. The best way to learn APRS is to obtain a shareware copy of APRS software, load it, and experiment with it. You don't even need a radio or packet equipment to get started. If you can connect to the Internet, you can see the whole world on APRS!

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