The Elmer Booklet

for the New or Prospective Radio Amateur

with technical articles by Harry Ricker III (KC3MX)
updated and revised by Christopher Sylvain (KB3CS) July 2007


Welcome!

You are about to discover that you have chosen a hobby that is only limited by one's imagination. How is that for a blanket statement? Well, it is true. Amateur (Ham) Radio is all about communication. How you choose to communicate and what you say is up to you (with only a few common sense restrictions).

You will soon be able to make friends with people around the world or even carry on a conversation with astronauts in space. If you are technically inclined, you have opened the door to experimentation, and if you are not, you'll pick up a little "know how" along the way. You'll soon discover that you do not need an electronics degree to get a license; just a willingness to learn.

"What is an Elmer" is probably the first thing that you want to know. That same question was asked recently at a club meeting which I attended. Simply put, an Elmer is anyone willing to teach you something about Ham Radio. In other words, practically every Ham you meet can, in some way, serve as your Elmer.

This booklet was originally prepared in 1986 by Jeff Horlick (KZ3F) with help from Ron Rubin (then N3KQY) as a teaching tool for newcomers, and as a handy reference guide. You should find that it addresses many of the questions that you might have as you are first getting started. The revised booklet (which you are now reading) includes several technical articles by Harry H. Ricker III (KC3MX) and other members of the Montgomery Amateur Radio Club. At first glance, all of this material may be a bit overwhelming, but just keep in mind that this information will be useful to you, both now and in the years to come.

Enjoy yourself! I know you will.

Ron (K3RON), Jeff (KZ3F) and Christopher (KB3CS)

INDEX


HOW AMATEUR RADIO FITS IN

The Amateur Radio Service is for individuals who are interested in the technical side of radio and are able to provide emergency communications in disasters, all for the general benefit of the public. It is called "amateur" because it is strictly non-commercial; no business may be transmitted on amateur frequencies. The Amateur Radio Service is a voluntary, disciplined communications service guided by five traditional objectives:

  1. to provide emergency or public service communications when normal communications are disrupted

  2. to advance the state of the art

  3. to improve individual skills in radio operation

  4. to provide a reserve pool of qualified radio operators and technicians

  5. to promote international goodwill

Anyone, regardless of age, can qualify for an Amateur Radio license by passing Federal Communications Commission (FCC) examinations for the three progressive levels (FCC license class) of achievement open to new hams: Technician, General, and Extra. (Note: Two other classes of license, Novice and Advanced, still exist for licenses granted before April 15, 2000. No new licenses for these designations are now being granted.) Exams include tests of applicants understanding of the technical and practical aspects of the Amateur Radio Service. The higher the class, the more difficult the exams and the greater the privileges of the license.

* adapted from "The ARRL FCC Rule Book" published by the American Radio Relay League (ARRL) #9000 $12.95

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HOW TO GET STARTED IN HAM RADIO

  1. Buy a copy of "The ARRL Ham License Manual" ARRL #9639 $24.95 or “ARRL's Tech Q&A” ARRL #9647 $15.95

    These books are for the beginner. They contain all of the information needed for preparing for the Technician Class license exam, including theory and rules.

    American Radio Relay League (ARRL), Publication Sales Department, 225 Main Street, Newington, CT 06111-1494
    888-277-5289

  1. FIND A HAM, who is willing to answer questions about what to study, Morse code, when and where license exams are given, and equipment. You can find a Ham among your friends and neighbors or in the Montgomery Amateur Radio Club (MARC). Visit a MARC club meeting. Join a club. Join the ARRL. Better yet, join MARC and the ARRL.

  2. START A NOTEBOOK: Get a two-inch ring binder, tabbed dividers and plenty of paper. Borrow copies of magazines and make copies of articles of interest. Check the Customer Support section of manufacturers and suppliers websites for manuals and technical documentation or write to them asking for catalogs. Make a shopping list. Use Google to find web resources for your interest areas. PUT EVERYTHING IN THE NOTEBOOK.

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ORGANIZATIONS

Your Local Ham Club:

Montgomery Amateur Radio Club (MARC)

P.O. Box 611
Gaithersburg, MD 20884-0611

FCC License information and assistance:
Rocky Jones (KC4UXO) - 301-216-5210
Cathy Gleason (N3ICW) - 301-299-4671

National organization of Hams:

American Radio Relay League (ARRL)
225 Main Street
Newington, CT 06111
(860) 594-0200

Washington Metro area council of Amateur Radio clubs:

Foundation for Amateur Radio (FAR)
P.O. Box 1013
College Park, MD 20741

Important information about Academic Year 2009-2010 scholarships

Other Amateur Radio Clubs (ARCs):

There are over 50 Ham clubs in the Washington Metro area (50 mile radius) to satisfy any combination of Amateur Radio interests and geographical location. Among the clubs are: Montgomery Amateur Radio Club (Rockville), MADRAS (Kensington,MD), Rock Creek Amateur Radio Association, Prince Georges Amateur Radio Club, Frederick Amateur Radio Club, Northern Virginia FM Association, Goddard Amateur Radio Club, Potomac Valley Radio Club and National Capital DX Association.

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THINGS TO BUY AND READ (in order of importance):

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HAM RADIO EQUIPMENT STORES
Amateur Radio equipment, supplies, books, magazines, etc.
(in no particular order. Being listed here does not constitute an endorsement of the vendor)

Amateur Electronic Supply (AES)
28940 Euclid Ave
Cleveland, OH 44092
800-321-3594
440-585-7388

G and G Electronics
Jeff Goldman
8524 Dakota Drive (near Shady Grove Rd)
Gaithersburg, MD 20877
301-258-7373
used equipment, misc. parts and supplies

Hamcity.com (Jun's Electronics & Commline, Inc.)
5563 Sepulveda Blvd., Suite D
Culver City, CA 90230
800-882-1343
310-390-8003

Ham Radio Outlet (HRO)
14803 Build America Drive
Woodbridge, VA 22191
800-444-4799
703-643-1063
Wide range of Ham and Shortwave radio equipment on display
Ham Radio Outlet is a good place to visit on Saturdays. Many Hams hang out there and much experience and advice is available for the asking.

Home Depot (PVC pipe and brass fittings, copper wire, poly rope), Lowe's,
McMaster-Carr or other hardware stores

Radio Shack
cable, connectors, parts, etc. at
various locations throughout our area.
(Note: some stores are now more consumer product oriented and do not stock the full complement of experimenter and hobbyist products)

The R.F. Connection
Joel Knoblock W3RFC
213 N. Frederick Avenue, Suite 11-W
Gaithersburg, MD 20877
301-840-5477
cable, connectors, used equipment, misc.

Other component and equipment suppliers and information sources are available via the “MARCclub” del.icio.us web tag.

Magazines:

QST - Included in ARRL membership, every Ham should belong

CQ and sister publication CQ VHF - a comprehensive monthly look at broad based information and special interest aspects of Amateur Radio

Worldradio - Newspaper format, up-to-date info, DX and International News, Public Service, Humor

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Simple HF Radio station:

Check WANT ADS in QST, the Classified Ads at QTH.com and Radios On-Line at ARRL.org to get a feel for fair prices for used equipment. Ask at MARC meetings if anyone is selling equipment. Many bargains can be found at eBay.com. There are many Ham Fests (swap meets) in the area throughout the year.

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“What to Buy” - A List of Things to Buy and In What Order

Written by Jeff (KZ3F)

What to buy - HT

1)
1-1       handheld transceiver- recommend dualband 2m/440
1-2       car cord for DC power
1-3       extra battery

2)
2-1       speaker mic
2-2       better HT antenna - rubber duck, dipole, etc
2-3       mobile antenna - mag mount and/or through-the-glass
2-4       gel-cell battery
2-5       attic or outdoor antenna for home with proper coax and connectors
2-6       DC power supply

3)
3-1       amplifier
3-2       battery case shell for AA batteries
3-3       external speaker



What to buy - mobile

1)
mobile rig - recommend dualband 2m/440
mobile antenna

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W1AW

Located in Newington, Connecticut, W1AW is the Amateur Radio station of the American Radio Relay League headquarters. It transmits daily on-the-air code practice and bulletins of interest to radio amateurs.

Times are in Eastern Time (EST November to March and EDT March to November)


Time

Monday

Tuesday

Wednesday

Thursday

Friday






9 am

---

Fast code

Slow code

Fast code

Slow code







10am – Noon

Visiting Operator Time (daily)



Noon – 1:00 pm

Station closed



1:00 – 3:45 pm

Visiting Operator Time (daily)











4 pm

Fast code

Slow code

Fast code

Slow code

Fast code







5 pm

Code Bulletin (daily)







6 pm

Teleprinter Bulletin (daily)







7 pm

Slow code

Fast code

Slow code

Fast code

Slow code











8 pm

Code Bulletin







9 pm

Teleprinter Bulletin







9:45 pm

Voice Bulletin







10 pm

Fast code

Slow code

Fast code

Slow code

Fast code











11 pm

Code Bulletin


Morse Code (CW) Transmissions

Slow code practice is at 5, 7 1/2, 10, 13, and 15 words per minute.
Fast code practice is at 35, 30, 25, 20, 15, 13, and 10 words per minute (wpm).
Bulletin and Code practice frequencies are 1.8175 (1.8025 as of March 9, 2009), 3.5815, 7.0475,
14.0475, 18.0975, 21.0675 and 28.0675 MHz. 3.5815 MHz seems to be best in this area.

As noted above, W1AW will QSY on 160 meters to 1.8025 MHz beginning March 9, 2009.

Transmissions begin with a long series of QST QST DE W1AW. Bulletins are sent at 18 wpm.

Teleprinter Transmissions

Frequencies are 3.5975, 7.095, 14.095, 18.1025, 21.095 and 28.095 MHz.

Bulletins are sent at 45.45 baud Baudot, BPSK31 and MFSK16. (BPSK31 and MFSK16 replaced
AMTOR and ASCII, respectively, as of August 17, 2009)

Beginning Monday, March 15, 2010, W1AW will alternate the digital modes used for its digital bulletin transmissions.

The Tuesday and Friday Keplerian data bulletins will continue to be sent using just Baudot and PSK31.

The new digital schedule as of March 15, 2010:

MondayBaudot, PSK31, MFSK16
TuesdayPSK31, MFSK16, Baudot
WednesdayMFSK16, Baudot, PSK31
ThursdayBaudot, PSK31, MFSK16
FridayPSK31, Baudot, MFSK16

Given time constraints and bulletin lengths, all three modes may not always be transmitted.

Voice Transmissions

Frequencies are 1.855, 3.990, 7.290, 14.290, 18.160, 21.390 and 28.590 MHz.

Communications Emergency

Monitor W1AW for special bulletins as follows: voice on the hour, teleprinter at 15 minutes past the hour, and CW on the half hour.

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MODEL TWO-WAY CONTACT (QSO)

ASK A HAM TO EXPLAIN THE DETAILS

Calling CQ - (Morse Code)

CQ CQ CQ DE KA3NHB KA3NHB KA3NHB
CQ CQ CQ DE KA3NHB KA3NHB KA3NHB
CQ CQ CQ DE KA3NHB KA3NHB KA3NHB K

ka3nhb ka3nhb de w3cku w3cku KN

W3CKU DE KA3NHB NAME IS JEFF JEFF AND QTH IS GAITHERSBURG, MD.
GAITHERSBURG, MD. BT RIG IS KENWOOD TS430 AND ANT IS DIPOLE 5 FEET UP
BT HOW COPY ? DE KA3NHB KN

ka3nhb de w3cku r r r fb copy jeff bt name here is jim jim es qth is
rockville, md. rockville, md. bt ur rst is 599 599 bt rig is homebrew qrp
running 5 watts bt age is 39 es been a ham fer 30 years bt ar kn

W3CKU DE KA3NHB R R R FB JIM, NICE TO MEET U BT AGE HERE IS 40 AND BEEN
A HAM FER 10 MONTHS BT

--
--
--

W3CKU DE KA3NHB FB JIM BT TNX FER NICE CHAT ES HPE TO CU AGN 73 73 SK
W3CKU DE KA3NHB

r r r 73 73 jeff es cul sk ka3nhb de w3cku dum-dah-dah-dum-dum

DOT-DOT

See "The ARRL Ham License Manual" for abbreviations and special words.

When you make an error in sending:

Be sure to note in your log:

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What Is A Repeater?

You have probably heard the term repeater used by hams when they say, "I'll meet you on the 9-5-5 repeater", but you are uncertain as to what they are talking about. Simply put; a repeater is a means of extending the range of a radio signal by retransmitting (repeating) it.

An example of an ideal application of a repeater would be when two people would like to communicate with each other, but they each live in a valley with a huge mountain between them. It is a safe bet that they will not be able to talk to each other, because radio waves are blocked by that mountain. The solution is a simple one; put up a repeater on the top of the mountain.

The repeater operates when you transmit on one frequency, and it receives your signal and retransmits it on a different frequency. For example, to communicate with the ham on the other side of the mountain, you might both transmit to the repeater on 146.355 mHz and you would be able to hear each other on 146.955 mHz, which is the frequency that the transmitter retransmits both of your signals on. All modern day VHF and UHF radios are equipped to transmit on one frequency and receive on another.

Don't for a moment think that repeaters are limited to only mountainous regions. In areas like Washington, DC, we use repeaters to extend the coverage areas of low power radios like hand-held walkie-talkies (HTs) or mobile rigs (mounted in automobiles, boats, bicycles, airplanes, etc.) If you were to transmit directly to someone with say 5 watts of power, your coverage might be limited to 5 miles. A repeater, which has a very sensitive receiver, would be able to hear that low power signal and retransmit it at a power of perhaps 100 watts. So someone living in Gaithersburg who would normally be limited to talking with someone in Rockville, might utilize a repeater and be able to converse with someone in Springfield, Viriginia.

Repeaters are also used as a gathering place for Hams. It is not unusual to hear several hams conversing as a group during their morning and afternoon commuting. It is a great way to meet people, disseminate information, and ask for solutions to technical problems. The next section, taken from the ARRL repeater guide informs you of proper repeater etiquette.

A repeater is often used for public service activities. During times of emergency (severe weather, etc.) repeaters are used by civil defense authorized groups, such as RACES (the Radio Amateur Civil Emergency Service), to relay information and to coordinate relief efforts.

Repeaters can also be used to provide communication support for walkathons and other community events.

Many repeaters have "auto-patch" capabilities which allow you to make telephone calls of a non-business nature in instances where phone service is not readily available. This can be done using a simple hand-held or mobile radio, and can come in handy in times of emergency.

You will come to appreciate the many uses of repeaters, and you will also find that they are a great source of fun and lively conversation.

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Repeater Operating Practices (from ARRL Repeater Directory)

  1. Monitor the repeater to become familiar with any peculiarities in its operation

  2. To initiate a contact, simply indicate that you are on the frequency. Various geographical areas have different practices on making yourself heard, but generally, "This is (your call sign) monitoring" will suffice.

  3. Identify legally; you must identify at the end of a transmission or series of transmissions and at least every 10 minutes during the communication.

  4. Pause between transmissions. This allows other hams to use the repeater (someone may have an emergency). On most repeaters, a pause is necessary to reset the timer.

  5. Keep transmissions short and thoughtful, Your monologue may prevent someone with an emergency from using the repeater. If your monologue is long enough, you may time out the repeater. Your transmissions are being heard by many listeners including non-hams with "public service band" monitors or scanners; don't give a bad impression of our service.

  6. Use simplex whenever possible. If you can complete your QSO on a direct frequency, there is no need to tie up the repeater and prevent others from using it.

  7. Use the minimum amount of power necessary to maintain communications. This FCC regulation (97.313a) minimizes the possibility of accessing distant repeaters on the same frequency.

  8. Don't break into a contact unless you have something to add. Interrupting is no more polite on the air than it is in person.

  9. Repeaters are intended primarily to facilitate mobile operation. During the commuter rush hours, base stations should relinquish the repeater to mobile stations; some repeater groups have rules that specifically address this practice.

  10. Many repeaters are equipped with auto patch facilities which, when properly accessed, connect the repeater to the telephone system to provide a public service. The FCC forbids using an autopatch for anything that can be construed as business communications. Nor should an autopatch be used to avoid a toll call. Do not use an autopatch where regular telephone service is available. Autopatch privileges that are abused may be rescinded.

  11. All repeaters are assembled and maintained at considerable expense and inconvenience. Usually an individual or group is responsible, and those who are regular users of a repeater should support the efforts of keeping the repeater on the air.

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INTRODUCTION TO PACKET RADIO

by Larry Kenney, WB9LOZ (from W3INK BBS)
revised by KB3CS

Packet Radio is a relatively recent development in the world of Amateur Radio. If you haven't already been caught by the "packet bug", you're probably wondering what it's all about and why so many people are so excited about it. Well, continue reading, because you're about to find out.

Packet seems to offer something different from other facets of Amateur Radio, yet it can be used for everything from a local QSO to a DX contact hundreds of miles away (on 2 meters!), for electronic mail, message transmission, emergency communications, or just plain tinkering in the world of digital communications. It presents a new challenge for those tired of the QRM on the low bands, a new mode for those already on FM, and a better, faster means of message handling for those on RTTY. Packet is for the rag chewer, the traffic handler, the experimenter, and the casual operator.

A ham can get involved very easily with relatively small out-of-pocket expenses. All you need is a 2-meter transceiver, a computer or terminal and a TNC. Alternatively, a 2-meter transceiver, a computer with serial port and sound card, an inexpensive computer-radio interface (“RIGblaster” or equivalent) and DSP software (“MixW” or equivalent). You probably already have the two meter rig and a computer of some kind, so all you need to buy is the TNC for a bit more than $100 or a computer-radio interface (about $60) and DSP software (about $40), The TNC is the Terminal Node Controller, the little black box that's wired between the computer and the radio. It acts very much like a modem when connecting a computer to the phone lines. It converts the data from the computer into AFSK tones for transmission and changes the tones received by the radio into data for the computer. Whichever method you use, TNC or DSP, it's a simple matter of wiring up a plug and a couple jacks to become fully operational.

Packet is communications between people either direct or indirect. You can work keyboard to keyboard or use electronic mailboxes or bulletin board systems to leave messages. Due to the error checking by the TNC, all of it is error free, too. (That is, as error free as the person at the keyboard types it.) As the data is received it's continuously checked for errors, and it isn't accepted unless it's correct. You don't miss the information if it has errors, however, because the information is resent again.

The data that is to be transmitted is collected in the TNC and sent as bursts, or packets, of information; hence the name. Each packet has the callsign or address of who it's going to, who it's coming from and the route between the two stations included, along with the data and error checking. Since up to 256 characters can be included in each packet, more than three lines of text can be sent in a matter of a couple seconds. There is plenty of time between packets for several stations to be using the same frequency at the same time.

If all of this sounds confusing, don't let it bother you, because that little black box, the TNC, does everything for you automatically. Packet might seem very confusing at first, but in a day or two you're in there with the best of them. Mailboxes, bulletin board systems, and the packet networks allow you to work stations hundreds of miles away using just a low powered rig on 2 meters or 70 cm. The world of packet radio awaits you!

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The following is a series of articles originally written in 1993 for the Elmer Booklet by Harry Ricker, KC3MX

Articles Index

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GETTING ON THE AIR WITH AMATEUR RADIO

After you have passed your license test and the VE has forwarded your completed Form 610 to the FCC, you have perhaps a few days before your license is issued via the Internet. As soon as you see your license application has been granted, print out the report from the FCC Universal Licensing System (ULS) database for your records. The official license document from the FCC can take six to twelve weeks to arrive by mail. This article will help you plan and set up a two meter mobile station and a simple HF station at home.

Getting on two meters is the easiest first step. You can buy a complete self contained amateur radio station in the form of a two meter handheld or HT. This comes complete with speaker, microphone, antenna, and power supply in one tiny handheld package. When you buy your first handheld, be sure that it includes a battery charger as part of the basic package. Buy a second battery so you will always have a fully charged battery available. This basic HT package is fine for use at home and for pedestrian mobile operation near a repeater. But for mobile operation in a car, you will need an external mobile antenna, a power adapter, and a speaker microphone.

A disadvantage of the HT is that it does not work well inside a car. You will need a 5/8 or 1/4 wave external antenna for your car. Choose a 1/4 wave model if you have a garage for your car or use a parking garage regularly. Purchase a cigarette lighter adapter to power your HT in the car so you will not have to operate using the HT battery. A speaker-microphone is recommended for use in the car because it is easier to operate than the entire HT while driving. The HT system described above is recommended because it gives you the flexibility to operate pedestrian mobile, for example at a public service event, as well as in your car. It is a good way to start in amateur radio on two meters.

Setting up an HF station in your home sounds simple but you will have to carefully plan your system in order to achieve good results. Your station will consist of an antenna, RF transmission line, HF transceiver, and accessories. Your single most important decision is your choice of an antenna. Choose a 10 meter dipole for your first antenna. It is small, only 16 feet long, and can be easily constructed from simple materials. It can be used indoors as an attic dipole, or outside between two trees.

Think about how you will mount the antenna before you begin construction. Use a tape measure to verify that you have enough space. Determine where you will place your transceiver and where you will mount the antenna, and then measure the distance needed to feed your antenna. Buy a preassembled RG-58 coaxial cable assembly with the PL-259 connectors attached. Be sure it is longer than your distance measurement by about 10 feet to insure it is long enough.

You may be tempted to buy an expensive new HF transceiver. But before you do, visit a hamfest to see what is available. Check used equipment advertisements and call local ham stores to find out what used equipment they have. A used transceiver about 10 years old should cost you about $550 to $650. This is half what you will pay for a new rig.

Consider a tube type transceiver if you are technically inclined and have a good knowledge of electronics. A solid state transceiver is a good choice if you are uncomfortable with a complicated tune-up procedure, and prefer simple no-tune operation.

For your first rig, you should select a transceiver which offers simple operation. Don't make your choice based on the number of memories or the number of features, make your choice practical. Select a transceiver which has the basic necessities such as: all band coverage, a narrow band CW filter, good sounding audio, and above all a reputation for performance. Ask questions when you negotiate the purchase. Talk to experienced amateur operators and get their opinions before you decide which rig to buy.

A meter capable of both power an SWR measurements is a necessity. You will need one to tune your antenna and verify operation of your transceiver. This meter should be capable of operation in both the HF and VHF frequency bands. A microphone usually is provided with the transceiver, but you will have to buy a CW key. A straight key is best for starting out. While most modern transceivers have internal speakers, they are usually not adequate. You should get a large high quality speaker for your transceiver to improve its audio output.

Optional accessories which you should consider purchasing but are not necessary are a 24 hour clock which can be set to universal time, a world map showing DX countries and call signs, an ARRL type logbook, and an antenna tuner. A low pass filter will be needed for older tube type radios which do not include an internal low pass filter. Most solid state transceivers have internal filters. A high pass TVI filter for your TV set may be needed if your family will be watching TV while you operate.

After you have assembled your station, you will want to fire it up to see how it works. A dummy load antenna will allow you to do this without transmitting a signal on the air. Practice tuning up your transceiver into a dummy load before you load into an antenna. Before getting on the air, you will need to practice sending CW. Use your transceiver's CW sidetone to practice sending CW. Turn the power down to zero output or transmit into a dummy load. When you practice sending CW, write up a script for a typical QSO which includes your name, location (QTH), equipment you are using (rig) and comments on your age and the weather (WX). Practice sending requests like, please send slowly (QRS), please repeat your name, your QTH again please QRM, and missed your last transmission.

Practicing this will help you to get through your first CW QSOs.

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TUNING YOUR ANTENNA

The fun part of antenna building is the design, construction, and erection of your antenna. Antenna design and construction is one of the most creative activities of amateur radio. But, every antenna project faces a critical moment of truth when RF power is applied to the antenna and the SWR is measured. If you think that your new antenna should work perfect the first time you apply power, you will probably be disappointed when you discover that the antenna SWR is higher than you planned. Even if you carefully calculated the length of the antenna, and measured the length very carefully, you are likely to find that the SWR is not acceptable. You will need to tune your antenna. Tuning is the hardest part of antenna construction and this article will help you do it quickly.

The most important step in tuning your antenna is to design a tuning method for your antenna when you are planning its design and construction. During the design phase, determine how you will adjust the length of the antenna elements. If your antenna is a dipole, you will need to change the lengths of the two sides of the antenna. You will also need to lower the antenna to the ground in order to make the adjustments. If your antenna design must work the first time without any adjustments, then it is not a very good design.

Your design should include a method of lowering the antenna for tuning adjustments, and a means for adjusting the element lengths. When you raise your antenna the first time, do not make it difficult to adjust the element lengths. Make sure you leave some wire at the ends for making your antenna longer, and do not tie the wire into knots that require a lot of effort to change when you trim the antenna. I suggest that you install the end insulators after you have found the correct length of your antenna. Use thin rope through loops in the antenna wire to hold up your antenna during tuning, and attach the insulators after you have determined the correct length.

Before you apply RF power to your new antenna system, make sure that you carefully inspect all your connections and the connectors. Use a volt-ohm-meter to check for shorts in your transmission line by measuring between the conductors. Also check to be sure that you have installed the connector properly by checking for continuity between the connector and the antenna elements. After everything checks out OK, connect your transmission line to the antenna jack of your SWR meter and the transceiver to its jack. Then set your transceiver to CW mode, tune to the desired antenna center frequency, and adjust the output power to minimum.

Set the SWR meter for minimum sensitivity and key your transceiver. Adjust your SWR meter sensitivity for a full scale reading. If necessary, increase the transmitter power setting until you achieve a full scale reading. You should always use the minimum power needed to achieve a full scale reading so that you don't cause interference. When you transmit to make SWR measurements, be sure to check that the frequency is not being used by other stations.

Your first SWR reading should tell you whether the antenna is working. Set your first test frequency to the design center frequency of your antenna. If your SWR measurement is off the measurement scale, usually greater than 5, then there is probably something seriously wrong with your antenna that tuning will not correct. Check your connectors and the connections at the feed point. Usually a very high SWR reading indicates either a short or an open circuit. You may have a cold solder joint somewhere in the system so reapply the soldering iron if you can't quickly find the problem. A common problem is the shield shorted to the center conductor in PL-239 type connectors. Also check to see that you have soldered the center conductor properly and that the center conductor is not broken.

If your first reading gives a low SWR of near 1, then you are very lucky. But, don't assume that everything is OK. Your antenna may not be working even when you have a low SWR. Check the SWR across the band. You should see the SWR readings rise as you increase and decrease the frequency from the design center frequency. If you don't verify a rise in SWR as you move away from the center frequency, then you have a problem in your antenna. It usually occurs when the antenna has fallen back down on the ground by accident. If your measurements show that the SWR behaves correctly, you have successfully completed your antenna.

If your first SWR measurement is between 2.5 and 5, you may have a problem that can't be corrected by tuning. SWR's in this range are too high to be caused by tuning error, and may be caused by bad connections at the feed or by unequal element lengths. Lower your antenna and verify that the feed connections are good and remeasure the element lengths to verify that they are correct. If everything checks out OK, then you may have a problem with the location of your antenna. If it is close to metal objects, trees, power lines, or wires, you may have detuned your antenna by locating it near these objects. In this case tuning may fix the problem.

Your goal in tuning your antenna is to place its resonant frequency at your desired operating frequency. The resonant frequency is the frequency for which the SWR is a minimum, usually at an SWR of 1. To decide whether your antenna is too long or too short you need to measure the SWR at different frequencies to see how it changes with frequency. When the antenna is too long, it has a resonant frequency lower than the design frequency. In this case, the SWR increases as the measurement frequency is increased from the design frequency. When the antenna is too short, it has a resonant frequency higher than the design frequency, and the SWR decreases as the measurement frequency increases. To determine whether your antenna needs to be lengthened or shortened, you need to measure the SWR at several frequencies across the band and record the results.

Your measurement results should show clearly whether your antenna is long or short, but the hardest part of tuning is determining how much to lengthen or shorten the antenna. If your SWR is high at the design frequency, then you will have to make a large change in the length of the antenna. If the SWR is near 1, then you will make only a small change in length. The actual amount of the change will depend on the frequency and the amount by which you need to shift the resonant frequency.

Tables and formulas which give the length of an antenna for different frequencies should be used to decide how much to trim your antenna. Tables and formulas for quarter wave length antennas are recommended when adjusting dipoles, because they specify the length of the sides of the dipole, rather than the total length. This simplifies the calculations, because you don't have to remember to divide your length corrections by a factor of two. To calculate the tuning correction, estimate the resonant frequency of your antenna using the SWR measurements. Then by using the tables or antenna formulas, determine the antenna length for this frequency. Compare this length with the length of your antenna. The difference in lengths will tell you how much to lengthen or shorten your antenna. Remember, that you shorten the antenna to raise its resonant frequency and lengthen it to lower its frequency.

After you have determined the amount of trimming, make the changes and return the antenna to its position. Repeat the antenna SWR measurements to determine the new resonant frequency. Your new resonant frequency should be very close to the desired value. However, if not, trim the antenna again and repeat the procedure of trimming and measuring SWR until your antenna is resonant at the desired frequency.

Sometimes the tuning procedure does not yield an SWR of 1 at resonance. In this case the minimum SWR may be only 1.5. This is OK but, if it is higher than this you should determine if something is wrong with your antenna. One thing to check, is to verify that both sides of your dipole are the same length. It is easy to make a mistake that gives you a dipole with unequal sides and this will cause the SWR at resonance to be higher than one.

With some experience, you should be able to quickly tune all your antenna projects. Tuning your antenna is the final step that allows you to achieve good antenna performance. Don't skip this step by thinking that your antenna tuner will do the job for you. If your antenna is not properly checked out and tuned, your antenna tuner may be loading up a malfunctioning antenna.

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MEASUREMENT OF TRANSMITTED POWER

When does an accurate power meter give the correct output power of your transmitter? The answer is only when the VSWR is 1:1. This means that your expensive power meter isn't much better than a cheap one if you don't use it properly. If your VSWR is high, you may be transmitting less power than you think, here's why.

If your power meter reads an output power of 100 watts and a VSWR of 3:1, you might think that this is your transmitter output power. But you would be wrong because the reflected power due to the antenna mismatch causes your meter to include the reflected power along with the transmitter output power in your meter reading. For a VSWR of 3:1, twenty five percent of the power your meter reads is reflected power. Therefore, your transmitter power is 75 watts.

Some people think that the above result must be wrong, because the meter reads the transmitter output power directly since it is located at the transmitter output. Furthermore, if the transmitter puts out 75 watts, then why does the meter read 100 watts? The reason is surprising, the reflected power from the antenna mismatch is reflected back from the transmitter output and adds to the original 75 watts to give a total of 100 watts at the meter.

When making power measurements, you must be careful to avoid power measurement error due to VSWR on your transmission line. There are several ways to do this. If you can measure the reflected power directly, then you can measure the forward power and then the reflected power and subtract the reflected power to obtain the transmitter output. Another method is to measure the VSWR and the forward power and then use a chart such as Table 1 to convert VSWR into percent transmitted power. Table 1 can also be used to find the reflected power by converting VSWR into percent reflected power. The reflected power is then subtracted from the forward power. If you don't have a meter that reads reflected power directly and you don't want to make the calculation every time you measure power, the following method can be used.



TABLE 1: THE EFFECT OF VSWR ON TRANSMITTED POWER











VSWR

RETURN LOSS
(dB)

TRANS LOSS
(dB)

TRANS POWER

REFLECTED PWR






1.0

INFINITY

0.0000

100%

0.0%



1.1

26.4

0.010

99.8%

0.2%



1.2

20.8

0.036

99.2%

0.8%



1.3

17.7

0.075

98.3%

1.7%



1.4

15.6

0.122

97.2%

2.8%



1.5

14.0

0.177

96.0%

4.0%



1.6

12.7

0.238

94.7%

5.3%



1.7

11.7

0.302

93.3%

6.7%



1.8

10.9

0.370

91.8%

8.2%



1.9

10.2

0.440

90.4%

9.6%



2.0

9.5

0.512

88.9%

11.1%



2.5

7.4

0.881

81.6%

18.4%



3.0

6.0

1.249

75.0%

25.0%



3.5

5.1

1.603

69.1%

30.9%



4.0

4.4

1.938

64.0%

36.0%



4.5

3.9

2.255

59.5%

40.5%



5.0

3.5

2.553

55.6%

44.4%



5.5

3.2

2.834

52.1%

47.9%



6.0

2.9

3.100

49.0%

51.0%



6.5

2.7

3.351

46.2%

53.8%


When you measure your transmitter power, place your power meter between your transmitter and your antenna tuner. Before you measure your power, adjust the VSWR to 1:1 and then take the forward power meter reading. Because the tuner adjusts the VSWR to 1:1, the power meter reading is correct. The reflected power in this case is zero.

The above methods are adequate when you want to know the transmitter output, but what you really want to know is how much power you are transmitting from your antenna. If your transmission line has a very low loss at your transmitting frequency and you don't use a tuner, the answer is simple. Your transmitted power equals your transmitter output power which is measured using one of the above measurement methods. If you use a tuner, the losses in the tuner must be determined and then the transmitted power is calculated as the ratio of tuner input power to output power. This ratio is the tuner loss in decibels converted into a ratio.

If your transmission line has loss and your VSWR is 1:1, the loss factor is the ratio of the power measured at your transmitter to the power transmitted. This ratio is calculated from the matched transmission line loss by converting from decibels to a ratio.

When your transmission line has loss in it and the VSWR is not 1:1, the problem is more complicated. One method is to calculate your transmitted power as before for the case when the VSWR was 1:1. However, the loss of the transmission line is higher when the VSWR is greater than 1:1. The usual method to calculate the transmission line loss when VSWR is not 1:1 is as follows. First, determine your 1:1 or matched transmission line loss at your operating frequency by using a loss table in the ARRL Handbooks. Multiply the loss per foot by the length of your transmission line. Second, determine the actual VSWR at the antenna. The ARRL Handbooks give a graph of input VSWR versus load VSWR to permit you to determine the VSWR at your antenna. The input VSWR is your measured VSWR at the transmitter. Third, determine the additional loss due to your VSWR at the antenna, determined in step two, using the graph of additional loss versus load VSWR in the ARRL Handbooks. Fourth, add the additional loss to the loss for a matched line to get the loss for your transmission line. Finally, convert the transmitter output power into power delivered to the antenna by converting the loss in decibels to the ratio of transmitter input power to transmission line output power.

The above method can be simplified by the use of Table 1. For corresponding values of VSWR, Table 1 gives the values of the reflection coefficient in decibels as return loss, and the transmission coefficient in decibels as transmission loss. To find the power delivered to the antenna the following method is used:

When you use a tuner, the above methods can still be used as long as your power meter is located at the tuner output. This may be more accurate than trying to measure the loss in the tuner or using the value taken from the manufacturers specifications. If you use your power meter between the transmitter and the tuner, the following method is used to determine the transmitted power at the antenna:

If you want to measure your tuner loss, the following method should be used:

After reading this article two really important facts should be remembered:

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CALLING CQ

Calling CQ is the first step in establishing amateur radio communication. You can answer a CQ sent by another station, or you can call CQ and listen for an answer. CQ, a radio code from the early days of radio, is used by radio amateurs as an invitation to establish communication. The communication established by the CQ call can take many forms. The communication which is established is called a QSO, pronounced “CUE-so”, from the Q-signal. When a QSO has been completed, an amateur operator refers to the communication as having "worked the station in a QSO", or just "worked" the station.

Operating procedure manuals have traditionally discouraged the use of the CQ call. For example, The 1964 ARRL Handbook does not give a procedure for calling CQ. The Handbook advises you to answer a CQ call but does not provide instructions for calling CQ. Later versions of the Handbook correct this deficiency, but advise you to listen for someone else calling CQ first. Calling CQ is a tradition of amateur radio. When you want to make a contact with another station, you should call CQ.

To avoid interfering with other stations, follow these steps before calling CQ. First, find a clear frequency - one that is not being used. Then listen for a minute or two. On phone, key your transceiver and transmit: "Is this frequency in use?". On CW transmit, "QRL?". Listen for an answer. If none, try again. If you get an answer, move to another frequency and repeat the process. On CW you may be answered with the letter "C", which means - yes, this frequency is in use. You may also be answered with QRL, which means the same thing. If you don't get an answer, then the frequency is clear and you can call CQ.

The CQ call consists of four parts: the CQ code, a qualifier code, your call sign, and an end code. The CQ code is an invitation to call you. Without a qualifier code, CQ means that you are inviting any station to call. When a qualifier code is used, you are transmitting a qualified invitation. Only stations which meet the qualification are invited to call. For example, a qualified CQ call used during contests is, CQ Contest, which invites only stations participating in the contest to call. On phone, it is the custom to say "this is" before your call sign. On CW the code "DE" is used. During contests, the CQ call is abbreviated by deleting "this is" before your call sign because it is implied by the format of a CQ call. On phone, the end code commonly used is "over" or "standing by for your call". The end code is not necessary and is usually deleted for contest calls. On CW, the code "K" is used to end the CQ call.

On FM repeaters calling CQ is sometimes discouraged. Don't let this deter you. CQ is the only invitation for any station to call. Use of "listening" and "monitoring" in place of a CQ call is ambiguous. There is a procedure for transmitting an invitation to communicate - calling CQ. You will always be correct when you use it.

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OPERATING QRP

QRP, from the Q-signal which means reduce your power, emphasizes the challenge of low power operation as an alternative to the use of high power stations. Originally, QRP meant amateur radio operation with a power level of 5 watts or less, but today QRP operators, called QRPers, embrace more than just low power. They construct their own rigs, operate using alternative energy sources, operate in the wilderness with backpack rigs, compete in QRP contests, cherish CW, experiment with antennas, and carry on the traditions of amateur radio which emphasize experimentation and rolling your own equipment. Defined simply, QRP is doing more with less, by building your own equipment, getting it on the air, and making contacts using low power.

To a QRPer, doing more with less is the main objective, but why would any ham willingly confine himself to operate with low power? If you make it difficult to communicate, where's the fun? This is a common reaction of high power hams. If you think that 100 watts is low power, you will be amazed at what you can accomplish with 5 watts.

While most QRPers use low power for the fun and challenge, there are practical reasons for QRP. First, is the need to reduce interference. If you live in a modern townhome or apartment, QRP may be the only way to get on the air without interfering with your neighbor's appliances. A second reason is the simplicity of the homebrew QRP rig. Simple QRP CW transceivers can be easily constructed using readily available parts. These rigs provide the thrill of making contacts using equipment you personally designed and constructed. A low cost CW QRP rig can get you on the air for a lot less than an expensive commercial transceiver. Even if the performance is poor, the thrill is greater when you make a contact using a homebrew rig.

QRPers embrace alternate energy operation in a big way. A QRO (high power) rig is useless during an emergency when commercial power is out. QRP has a big advantage here, because it uses emergency power sparingly, and encourages use of alternative noncommercial power sources such as solar or wind power. A simple QRP emergency station power source can be implemented using a automobile battery and a charger. QRP operation with battery power is an excellent emergency solution, because QRP conserves energy for longer operation by doing more with less.

QRP contesting is one way QRPers test the effectiveness of their stations. QRP Field Day operation highlights the effectiveness of emergency operation at QRP power levels. But, QRP contests are also lots of fun. QRP contests contrast the competitive, frenetic, high interference environment of big contests with an enjoyable contest experience. If you are disgusted by high power, fast paced, QRO contests, then try QRP. The pace is slower, the contacts friendlier, and the experience is positively rewarding.

Combining another hobby with amateur radio is one way we can enhance the enjoyment of our hobby. QRPers have pioneered the combination of backpacking and QRP to create a wilderness amateur radio experience. The objective is to backpack your QRP portable station to a wilderness mountaintop and see how far you can work. Wilderness operation encourages innovative low power rigs which operate efficiently from battery or solar power. Since weight is important, this type of operation encourages light simple rigs, with a minimum of accessories, and efficient wire antennas.

As you may have surmised, almost all QRP operation is via CW. This does not mean that QRPers do not operate QRP on SSB, but just that CW operation is a more effective way to accomplish the QRP goal of doing more with less. Simple low cost CW rigs, built by QRPers, are easily constructed for CW operation, while SSB rigs are more complex, costly, and difficult to construct. QRP contests are mainly CW affairs, while QRP nets are mostly all designed for CW. If you would like to participate in a net, but are not interested in traffic handling, QRP nets provide a means to learn net operation, and upgrade your code speed, while testing the effectiveness of your QRP station. Finally, your CW QRP experience will teach you one of the best lessons of amateur radio, you will learn to cherish CW because it is fun.

As you may have guessed by now, QRPers don't like big towers and huge beams. Doing more with less means that QRPers like to get the most from simple wire antennas. Large loop antennas are popular along with dipoles, and long wires. QRPers like to get their antennas up high in the air and experiment with wire beams. Backpack QRPers like this approach because there is lots of room for big wire beams in the wilderness. QRPers also use indoor attic antennas. Despite what you might think, indoor attic dipoles work well with QRP. The author has worked New Zealand two way QRP - meaning both stations were operating QRP - using an attic dipole. He also works mobile QRP, a real challenge. For those who want to try something different, working CW QRP mobile is great fun, particularly when you are working DX.

Before you can enjoy the fun and challenge of QRP, you have to upgrade to general. You will find QRPers operating on the following CW frequencies:

3560, 7040, 14060, 21060 and 28060 kHz.

Check out QRP net operation, by checking into the NEN QRP Net which meets on Saturday mornings at 8:00 AM on 7040 KHz. QRP contests are announced in QST and other magazines, look to see when one is scheduled. The most popular contests are the QRP ARCI spring and fall contests which occur in April and October. QRP is great fun. Don't be put off by the idea that low power operation is difficult. Many QRPers operate at milliwatt and microwatt power levels. Remember that you can do it with patience, and persistence. QRP adds to the fun of ham radio, you are welcome to join in.

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SPORADIC E PROPAGATION

Looking for excitement? Would you like to operate VHF on low power with small antennas, yet be capable of transmitting half way across the country with 40dB over S9 signals? Are you thinking about selling your 10 meter rig, because the low ebb of the sunspot cycle has caused 10 meters to fade out? If you are at least a technician class licensee, you need to know about sporadic E propagation as an answer to these questions.

As a technician, you may think that you can't enjoy the excitement of HF propagation. How can you work distant states when you are mostly restricted to the HF and VHF frequency bands above 28 MHz? All the excitement of HF long distance propagation is available to you on the six and ten meter bands through sporadic E propagation. With low power rigs of only 10 watts, and simple antennas, you can work states 1,000 miles away. This propagation mode keeps 10 meters hopping during the bottom of the sunspot cycle. Sporadic E can enhance the excitement and fun of amateur radio, here's how.

Sporadic E is a propagation mode which occurs due to the ionization of the E region of the ionosphere. The ionization occurs in an unpredictable sporadic manner, hence the name sporadic E. The ionization when it occurs is very intense and is capable of reflecting VHF radio waves for distances up to 1,000 miles in a single hop. Frequencies across the spectrum from low HF to high VHF can be propagated using the sporadic E mode, but the effects are the most dramatic on 10, 6, and 2 meters. Yes, you can use sporadic E on 2 meters to work long distances beyond line of sight. Because the ionization is very intense, signals are very strong, even when low power is used with low gain antennas. To exploit the advantages of sporadic E, you need to know when it occurs.

Studies show that sporadic E is not random. It occurs most frequently during the months of May, June, July and August. Frequency plots show that it peaks in June and then again in December, but the December peak is rather weak. Sporadic E primarily occurs during the summer months. That is when you should be looking for it. Sporadic E also occurs during certain times of the day. There are two periods of activity, during the morning from about 9:00 AM to noon local time, and from about 6:00 to 9:00 PM in the evening.

Sporadic E is not affected by sunspots. Band openings are always possible during the summer beginning in May. You should look for them, and call CQ occasionally even when the band seems dead.

Set your squelch to monitor for calls. On 10 meters, try scanning with your squelch on between 28.300 and 28.500 MHz for SSB or call on 29.600 MHz for FM. On 6 meters, tune to the calling frequency 50.125 MHz for SSB or 52.525 MHz for FM. When the band is open, the excitement begins.

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