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Steve Tarr, KD7MRX
One of KD7MRX’s many amateur rockets. Inside is a 70cm tracking beacon, GPS receiver, APRS link to a simple TNC, and a 2 meter transmitter (and a parachute and engine)
The first question, always, is "How high does it go?" Anyone who flies high-power model rockets as I do knows the answer to that one: "It depends." High-power rockets can be as little as one foot to more than 20 feet long and can weigh anywhere from one to 200 pounds at liftoff. My own rockets are between three and six feet and between two and ten pounds, a little below the median for our club.
The second and third questions are usually "what kind of motor do you use?" and "where do you fly them?" Most high-power model rockets use composite-propellant motors similar to the space shuttle's boosters. The motors have about 100 times the total power of the Estes or Quest model rocket motors that you see in stores and may have flown yourself.
It takes a big field to fly these rockets. You can't just use a local park, schoolyard or athletic field! I fly with other members of OregonRocketry from a site near Brothers, Oregon, about 40 miles east of Bend. The club arranges for FAA waivers, landowner permissions and some on-site facilities. Flying with a club is a lot like amateur field day. Some people are there to socialize, some are there to set up equipment and run the launch, some are preparing to push themselves and their rockets to a new limit, and others are there just to fly an old favorite for the 20th, 30th, or 40th time.
The fourth question is asked by the rocketeers after every flight: "Where did it go?" That's an especially important question at our site which is mostly soft sand and fine gravel covered in sagebrush. Although it's fairly flat, there are enough bumps and dips to hide even a large rocket lying on its side. Sagebrush has an almost magical ability to capture and hide rockets as soon as they land. Friends and family members with good eyesight are a help, but even they can't always track a small rocket more than two miles away. Rocketeers have tried a variety of technical solutions. Some people have mounted strobe lights in the nose cone or packed beepers or buzzers as a payload, but those of us who are also amateur radio operators have a better way.
After I lost a favorite rocket at Brothers, I decided that I needed a better way. I obtained my Technician-class ham license the next spring and bought a low-power tracking transmitter, a handheld yagi, and an iCOM Q7 handheld for use as a tracking receiver (and as a general-purpose handi-talkie). The transmitter is tiny, less than three inches long and an inch in diameter. It sends periodic "beeps" and my callsign on a fixed frequency in the 70cm band. The output power is only a milliwatt or so, but that's enough to track a rocket for several miles.
Since then, I've built similar units of my own to put in each of my rockets. I've lost only one transmitter-equipped rocket, and that was because I forgot to turn on the transmitter before launch. I get a lot of interest from other rocketeers each time I show up with my equipment. It's a chance to do a little public relations work for the whole amateur radio hobby. Another ham in the club uses a similar tracking system and last month we won over our first "convert". One of the other OregonRocketry members passed both his Technician and General written exams and is now working on the code test. At least two others are studying for their exams and several others are talking about it.
If we can track the rockets via radio, how about sending back some useful or interesting information as well? Some amateurs in our club have flown an ATV transmitter in a rocket. Another has flown an audio recorder, and a company in Holland sells a complete rocket telemetry system. That got me interested in the idea of having the rocket report its position over the radio. I built an APRS encoder and a KISS-mode TNC from plans published in QST.
After some trials, I decided that APRS is just the ticket for sending telemetry from a rocket, except that you need a TNC and a computer on the ground to decode the data. I didn't want to have to rely on either of those; I wanted the rocket to simply tell me where it was. Then one day I overheard a ham setting up a phone patch on a local repeater. The repeater was reading the telephone digits back over the air. Eureka! I could use a stored speech chip -- just like the one in the repeater controller -- to store my callsign, the digits "0"-"9" and a few key phrases. A simple microcontroller could read the position data from a GPS and pick the right phrases out of the stored speech chip to read the data over the air.
It took me another six months to put all the pieces together, write the software for the controller, and record the phrases in the speech chip. I used a Magellan 310 GPS to compute the rocket's position and the bearing back to the launch site, a PIC microcontroller to assemble the speech data, an ISD stored-speech chip to hold the fifty or so audio phrases I needed, and a 10mW FM transmitter module. I packed the whole mess (and it was a mess!) into a 4" diameter rocket along with an altimeter, batteries, and two parachutes. Then into the car and off to the launch site!
I flew the package on July 20. The flight was a qualified success. One of the parachutes didn't fully deploy, so the rocket landed faster than I expected. That meant that I didn't have much time to listen carefully to the signal on the way down, but I heard enough to confirm that the rocket was transmitting position and bearing. Having the rocket come down fast also meant that it landed close to the launch site; I didn't need the radio system to see where it had landed.
When the rocket landed, the change in antenna loading (because the wire whip antenna was lying on the ground) was enough to shift the transmitter frequency about 10kHz - out of the receiver passband. I didn't realize that until I had almost reached the rocket. The transmitter was still sending the correct position, but I hadn't heard it. Next time, I'll use a more stable transmitter.
And when I got to the rocket, the altimeter was beeping 2...8...8...0 feet. That was with a medium-sized motor for this rocket. With the bigger motor, it should go just short of a mile in October
'73 de KD7MRX. Fly high!
Links
OregonRocketry (OROC)
www.oregonrocketry.org
OregonRocketry is a non-profit Oregon corporation, organized to support hobby and educational rocketry. The club hosts two public launches each year at a site near Amity, Oregon and four public high-power launches each year at a site near Brothers, Oregon.
Northwest Rocketry
www.northwestrocketry.com
Washington High Power (WHiP)
We are closely affiliated with both these Washington area clubs.
The National Association of Rocketry
Tripoli Rocketry Association
These are the two national rocketry organizations. I'm a member of NAR (member #77956), other OROC members are Tripoli members or are "bilingual". You must be a member of one of these organizations to purchase high-power rocket motors.
All Hobbies
Ursula Gilkey (proprietor) travels to rocket launches all over the Northwest in her "mobile AP therapy unit" van.
Tammie's Hobbies
Beaverton hobby retailer; stocks a variety of low- and high-power rocket kits, motors, and components. This is where I go first when I need parts between launches.
Binder Design
Manufacturer of high-power rocket kits and components. My rocket is a Binder Excel Plus with a homebrew "stretched" payload compartment.
VE TESTING:
3rd Friday of Every Month , 6:30 PM.
(prior to regular club meeting)
650 NE Holladay Street, Portland.
Call Bruce McCain N7XB (503) 257-7320
email: N7XB@arrl.net
ARES MEETING:
No August Meeting
– Enjoy the Summer Break!
Next meeting September 27th at
Fire Station 2 4800 NE 122nd at 7PM
By Karl A. Kopetzky, K9AQJ
Metro Amateur Radio Club (MAC) member, Karl Kopetzky, K9AQJ, wrote the following reminiscence. Karl was 95 years old, had been licensed for 80 years (his first ticket was signed by then Sec. of Commerce Herbert Hoover), and on the air for 88 years. Karl became an SK a short time ago, but his article sheds some interesting light on the history and operation of early wireless stations.
It is a weird anomaly that as a nonagenarian I can easily remember – to the smallest detail – what I experienced when I was 5 years old and thereabouts, but cannot recall except with difficulty, what I ate for supper last night. So, I can easily recall what I went through when I was aged six, becoming involved in Spark Communications.
The summer of 1912 was a time when because of his involvement in Spark Communications anent the TITANIC Disaster, the country was hip-deep honoring David Sarnoff, as the N.Y. City wireless operator link between the TITANIC, the rescue ship, CARPATHIA, and the World Press.
Little did I know that on that 1912 Labor Day, a Central Park outing, when I was 2 months short of being 7 years old, would change my entire life.
Because it wasn’t unusual for me to meet a kid my age who was taking homebuilt wireless stuff out of his little wagon, and using it to pretend he was a Wireless Operator. He had built most of his wireless gear using an Instruction Booklet and a Catalog from the later to become the famous I.I. Co.
With my mother’s help I got the Instruction Book and Catalog; and went to work building my first ham, wireless station. I didn’t do too well; but for my birthday two months later, my Dad bought me the complete wireless transmitter and receiver parts, which I would assemble into a working ham, wireless station.
I did that. And my wireless station became my Pride and Joy even though I didn’t know code. Nevertheless, for the better part of the next 8 years I tried desperately to hear someone reply to my transmitted gibberish, which nobody did, if indeed anyone ever heard me.
But, I was hooked for fair: Wireless had become part of my life. I enjoyed wireless even if I didn’t get replies.
Just using the gear and trying to make it communicate was simply GLORIOUS to a 7-year old kid! In September 1920, eight years later, I matriculated into Phillips Andover Academy where I discovered it had a Ham Club Wireless Station, licensed as 1SW; and operated under the supervision of Prof. Freddy Boyce, the physics teacher.
Could I join the Club and operate 1SW? “Definitely!” said Prof. Boyce, “ But, first you’ll have to get your Federal Amateur Operator’s License.”
The Club lent its three Instructographs, which sent code from an included tape, to prospective Club members to learn the code at 10 w.p.m. to be licensed. And Prof. Boyce lectured on what was required to pass the written examination for the Conditional ham license.
Slowly, the code “came” to me. And I finally passed it under the watchful eye of Prof. Boyce; and wrote out all the correct answers to the examination questions. Three weeks later, I was legally a duly licensed ham. And best of all, I could operate the Club wireless station, 1SW, after instructions from Pro. Boyce.
Then two things happened in quick succession. I got a reply to a CQ call, which I really couldn’t answer, I was that excited. That changed very soon, and I had many QSO’s by spark! Several days later, in the current QST, “Calls Heard Section”, there it was for all to see and note. On a specific date, the “Calls Heard Section” stated that 1SW had been “heard” by Nauen, Germany. The date was when I was “on watch”. And it was my CQ the Nauen had apparently heard! At least, that’s what I boasted…. Repeatedly!
Since 1924, I have had a ham radio shack replete with the latest in ham gear from 2 through 80 meters with CW and later with that plus phone, which I have used constantly for 76 years. Nevertheless, for me, neither CW nor ‘phone have EVER been as GLORIOUS as was spark to a 7-year old kid, and later to a 15’year old teen-ager at Andover, transmitting with its 1-inch Spark Coil and Rotary Spark Gap!
Nothing has ever beaten that in my entire “ham life”!
By Ed Buress KC7GFX
APRS Display of W7LT on top of Kelly Butte
Turn on your handheld and set the frequency to 144.390. Hear those stations sending digital packet information? That’s not just standard run-of-the-mill packet you’re hearing, but a group of hams transmitting their position using APRS. Automatic Position Reporting System (APRS) relies on time and positional data transmitted by a group of satellites in earth’s orbit. These satellites were created as part of the Global Positioning System. Low cost hand-held receivers take the time stamp and positional data from the satellites, and turn it into a latitude and longitude, useful for finding your location on a map. The accuracy of one of the GPS units currently runs about 15 feet. Backpackers, boaters, and hunters can use this GPS data to navigate their way over land and water. Light aircraft owners have found them a convenient way to navigate to that next airport, or over a scenic site.
APRS takes the GPS data one step further by feeding the GPS unit to a ham transmitter. Not only can you locate your own position, but other hams can know your position as well. A few companies have started offering digitally equipped radios that allow both voice and positional data automatically. OK, so why would you want others know your position? Let’s say you’re part of a Search and Rescue team, your position would always be transmitted to the command post as well as other searchers. Tactical command would know your location and could direct the search team more effectively.
Races and walkathons can also benefit from APRS. Placing an APRS transmit package in the shuttle vans and supply vehicles can provide up-to-date information on their location. Voice communication can then be used for direction rather than information gathering. Having a chase bicycle at the lead and tail of the marathon can provide the coordinators with current positions and progress of the race. Displaying all this on a screen back at the coordination site can provide the organizers with information about which roads to close, where to allow traffic back thru, and where an emergency vehicle might be needed. Properly applied, APRS can become an important tool in community service activities of Amateur Radio. So at this point, you may be asking yourself, what do I need?
When APRS emerged into the PC world, it relied on readily available cheap hardware, primarily driven by DOS. Maps existed as crude representations of major highways, landmarks and larger surface roads. With 386 machines becoming available at reasonable prices, a supply and demand for better APRS maps and programs followed. Although these programs are still in use, and support for them in terms of better maps or updates to the program capability can still be found, better answers are now available. Pentium-based laptops are falling in price, and a diligent bargain hunter can find a Windows 95, or 98 capable machine for around $100. A CD Rom drive is a must if you want to run the latest mapping programs like Delorme’s Street Atlas.
Delorme, a supplier of Street Atlas, Topo USA and similar mapping software for the traveler has been used as the basis of a source of readily made, accurate, and relatively inexpensive source of detailed maps for APRS. Street Atlas utilizes a function known as “overlays” to help the user find their way. Normally, overlays are used to find libraries, restaurants, gas stations, hotels, and of course the ever-present Starbuck’s Coffee. Using these overlays, an enterprising software engineer was able to read the data stream from APRS and re-format it to look like an overlay to the software. What emerged was a highly detailed map, showing street level detail across the US with APRS operators popping up wherever their transmitted coordinates are.
Screen Shot from APRS +SA positional data page. Note the various fields that are available to quickly survey information available from the different APRS operators.
The look and feel of the application is much like other Windows programs, and lends itself well to “learning on the fly”, (from www.tapr.org/~kh2z/aprsplus/).
To run APRS +SA, you’ll need a machine capable of running Delorme’s Street Atlas. Windows 98 is preferred, but Windows 95 will do. A CD Rom Drive is necessary to load and use the available maps. A standard com port is necessary to connect to the TNC. If you already have a packet station capable of running windows, and a CD Rom drive, you’re just a software step away from receiving and displaying APRS operators on a highly detailed map.
One of the questions you should be asking is “am I showing my location to others, or am I looking to see where others are located?”
If you’re traveling across country, and you want your friends and family to be able to keep track of your location (or where the thief who took your car is currently located), all you need is a GPS, TNC and Transmitter. Your family members don’t even need to have their ham licenses to keep track of you. Websites like findu.com allow you to make your position available on a detailed map without the need for receiver, TNC, or mapping software.
Some handheld 2-meter radios now come with a built in TNC and all that is required is attaching a GPS. Groups like the Tuscon Amateur Packet Radio Society (TAPR) have offered kits like the “tiny-track” which are rudimentary transmit-only digital TNC’s. Connecting one of these to a GPS, and small transmit module can make a rather small package which is suitable for remote control devices, balloon launches, and amateur rocketry.
To receive the GPS locations, all that’s needed is a handheld, a TNC, and a display. Displays can be as simple as text displays, showing the latitude and longitude of the received signal, or they can be more elaborate, using the previously mentioned mapping software on a Pentium-class laptop. As mentioned earlier, even non-hams can get in on the action, using a web connection to view the last transmitted position of an operator.
The current version of Street Atlas will run about $50 retail, but used copies of version 4 and above can be had for about $10 (you need at least version 4 or better to run APRS +SA. A laptop will run anywhere from $100 on up, depending what you what features you want, and what type of deal you can run across. A used TNC like a Kantronics KPC-3 can be had for around $75. Add an antenna and handheld, and you’re in business.
After following the installation procedures for Street Atlas, next you’ll need a copy of APRS +SA. A shareware program, APRS +SA is available from http://www.tapr.org/~kh2z/aprsplus/. You can download the full version and use it off the shelf. Drawbacks for the unregistered version are that your port number, callsign, baudrate settings, and initialization file is not saved, and you will need to register to have all of these settings become permanent. You can still use the full version, but will have to type in each of these settings every time you fire up the application. Once the APRS +SA is opened up and configured, you can start up Street Atlas. What should happen is that you’ll see the starting location map displayed with APRS operators displayed as an overlay.
If you look around at the different fields of APRS +SA, you’ll soon notice that there is something else happening here… More than just “my current position” is shown. Weather data, what type of vehicle or fixed locations are displayed, as well as simple messages like “Hello from Anchorage, Mike AL7_ _, 14.280@2000+ GMT”. An HF contact can then be made using the short message that the operator beaconed over the APRS links. By similar methods, the current reported position of a tornado, hail storm, blizzard, chemical spill, floods, industrial accidents, or other natural and man-made disasters can be reported to give fellow operators a heads-up on local hazards. Each type of reported incident has it’s own associated symbol for the map. Since APRS is modeled on packet radio, point-to-point communications and “store and forward” methods are used to relay each received station to the next. If you haven’t tried APRS for a while, you might want to check in on what’s happening lately.
Ed KC7GFX
Regular Club Meeting Friday Aug.16th 7:30 PM
ARES Meeting No August Meeting!!
Club Net Monday’s at 7PM
ARES/RACES Net Wednesday’s at 7 PM
Club Breakfast Saturday Sept. 7th
ATV Day at HRO Saturday Sept. 14th
The August PARC Meeting will include a presentation on Amateur Positional Reporting System with (hopefully) a live display of APRS operators around the local area.
Please join us and learn more about APRS on Friday August 16th at 7:30 PM.
One Liberty Center 650 NE Holladay Street Portland, Oregon(A few blocks SW of the Lloyd Center)
Enter on South side of building, use the intercom to gain access to the building.
All hams are welcome to attend. Updates and changes will be announced on the PARC Net, Monday at 7 PM on the 146.840 Repeater. All hams are encouraged to check in!
Here is a Schedule of Nets for all interested.
All Nets are handled on the 146.840 repeater.
Sunday: Handi-Hams Net 7 PM
Monday: PARC Weekly Net 7PM
Wednesday: ARES/RACES Net 7PM
All Hams are welcome to check in or listen to any Net
(This is the second installment of a multi-part article reprinted with permission of the author Peter O’Dell, WB2D. CQ Magazine April and May 2002)
It is critical for the receiver to be well shielded, too. Just as you do not want stray RF coming out of the transmitter, you do not want stray RF getting into the receiver. Therefore, you will find similar shielding, bypassing, and decoupling at the receiver. It is also mandatory that repeater receivers have good selectivity in the front end. You want the passband of the front end to be as narrow as you can make it. At VHF and low UHF frequencies this usually means using devices called helical resonators. You won't find these in many of the rigs designed for home use. It is more important for a repeater receiver to have good selectivity than it is for it to have good sensitivity.
Motorola Receiver showing Helical filtering (top of photo) and input filtering (right of board)
If an off-frequency signal gets into the receiver, it will cause a problem known as desensing the receiver. For instance, if some of the transmitter's energy is leaking into the receiver, desensing will be constant. However, if it is coming from another source, desensing will only happen when the other transmitter is on the air. To the extent that desensing occurs, it will block out the weaker signals. In severe cases a repeater can be made virtually useless by desensing.
An associated problem is called inter-modulation distortion or IMD for short. Here the offending signal is the product of two or more off-frequency (often out-of-band) signals that mix in a nonlinear device. Put in plain English, this means that two or more signals happen to arrive at the same time at something that is acting like a diode, say a corroded connector or the front end of a poorly installed receiver or whatever. These signals then mix or heterodyne, and by chance one of the products falls into the input range of the receiver (or someone else's receiver).
Suppose there are three signals mixing to produce a product that is near a repeater input frequency. The interference will only occur when all three transmitters are on the air at the same time. This is a problem that can give repeater tech crews nightmares and often requires extensive detective work to track down. Eventually you'll hear hams talking about desensing and IMD. These are the problems they are talking about.
Obviously, the receiver and transmitter cannot be on the same frequency. The receiver frequency is called the input frequency, while that of the transmitter is the output frequency -pretty straightforward. The difference between the two is called the split, or separation. On two meters the standard split is 600 kHz. There is nothing magical about this particular frequency. It grew out of the maximum front-end passband of some of the early commercial receivers that were converted to ham use. The commercial rigs only had a few channel positions, and crystals were expensive. Say the local repeater was on 146.34/146.94 MHz. The average user would set up two channels (your input/output frequencies will always be the mirror images of the repeaters). First would be 146.34 transmit and 146.94 receive. The second would be transmit and receive both on 146.94. The reason for this was that when the repeater was off the air, locals could talk mobile to mobile on 146.94 simplex. Repeaters are a lot more reliable these days, and most groups frown on simplex activity on the output, and certainly on the input, frequencies.
Thus, 600 kHz became the standard split because of a historical accident. However, it is not the only split. Flip through the ARRL Repeater Directory and you will find repeaters with other splits--mostly 1 MHz. Most modern equipment is set up to easily handle these "odd-ball" splits. (In a future installment we'll look at the social aspects of repeaters, including the frequency coordination.)
One of the most desirable aspects of FM operation is what is called the capture effect of an FM receiver. What this means is that if two on-frequency signals show up at the same time, the stronger signal will "capture" the receiver. It will be as if the second signal was not there at all. The difference does not have to be significant either. Even when two signals are close to one another in signal strength, the stronger one captures the receiver. It makes for much more pleasant listening than on AM-based systems. On AM, signals 100 times weaker still cause annoying interference.
FM receivers also tend to have a fairly sharp cutoff in terms of signal strength. At a certain point a weak signal simply drops out. These two factors together give FM (and repeaters) the distinctive, limited coverage area. Cross that magic line, and you are "out of range". Terrain plays a big part in this, too. That point was driven home to me dramatically during the flight of STS-9, Owen Garriott, W5LFL'S inaugural manned-use of ham radio in space. The day after launch, Columbia was coming down over the western edge of the U.S., and officially we were not expecting him on the air for another few hours. However, Roy Neal, K6DUE, guessed that he might come on the air early and left his handheld tuned to Owen's frequency. Sure enough, Owen's voice came booming out of the receiver as he worked several West Coast hams. Roy was on the 6th floor of the Hilton Hotel across from Johnson Space Center. We later estimated that it was about 1300 miles, but there was nothing between the two radios except a few air molecules. Ah, the blessing (and curse) of a "tall tower".
Recently, I attended “Cub World” with my son Reed. For two nights and 3 days, we camped out and did a lot of fun activities at Scouters’ Mountain, located in Happy Valley, about 7 miles East of Clackamas Town Center. During the opening ceremony, our guest speaker from the local Cascade Pacific Council Office of the Boy Scouts of America related some interesting statistics, which apply to our club as well as the scouts. Trying to find out why enrollment in scouts had been declining in recent years, the National Scouting organization commissioned a study that was conducted by a marketing group. The number one reason they found why membership had been declining was because the parents had not received a personal invitation for their son to join. Although they had been able to present scouting in the cafeteria of the schools, had been able to send home an information packet and sign-up sheet with the scouts, somehow it was overlooked as an invitation, but rather “just another piece of paper wadded up in their son’s backpack”. It wasn’t homework due the next day, so it didn’t get a second look. On average, it took 4 invitations before a parent would sign up their son for scouting. Many of the invitations came from parents of scouts who were already signed up, telling their friends about how much fun their kids were having, and asking them if their son’s friend would like to go to the next meeting.
In Amateur radio, we face a similar statistic. Even though we have an increase annually of new operators, due to the attrition rate of Silent Keys and operators either forgetting or choosing not to renew their licenses, the number of licensed hams in the US was increased by only 230 last year. Much is the same with our club as well as others across the country. We have about 79 current members in our club, a pretty good size, but still makes it difficult to have enough funding to maintain our repeaters and service our newsletter base.
In order to help get the word out to the ham community, I would like each one of you to invite a friend to the meetings, and to take a look at joining our club. Don’t worry if someone from the club already asked them, remember…we’ll probably have to ask them at least 4 times before they’ll show up, or tell us to go away. Two of our members got together and bought a friend a membership in the club; It’s a good way to make someone feel welcome in PARC.
73, Ed KC7GFX
Thanks for the membership renewal since our last issue!
Jim Belt K7JIH
President: KC7GFX Ed Burress, e-mail: KC7GFX@arrl.net
Vice President: K7ZSK John Pinkerton
Director 1 Year: WA7AXO Bert Younglove
Director 3 Year: K7RUN John White
Recording Secretary: vacant
Treasurer: W7PR Pete Rodabaugh (503)-771-1773, e-mail: W7PR@arrl.net
Membership Sec.: KD7HDP Pat Kennedy, e-mail: KD7HDP@arrl.net
Station Trustee: KI7GA Tony Thornton
Other positions
Newsletter Editor/Publisher: KC7GFX Ed Burress
Webmaster: KD7HDP Pat Kennedy, e-mail: KD7HDP@arrl.net
Amateur Television (ATV) Day at Ham Radio Outlet-Sept. 14th
Come join Oregon Amateur Television Association (OATVA) at HRO on September 14th from 11 AM to 4 PM for a live demonstration of their ATV Repeater System. For more ATV info visit the OATVA web site at www.oregonatv.org. HRO is located at 11705 SW Pacific Hwy (99W), behind the Arby's restaurant.
No August Meeting for Multnomah Co. ARES Group. See you all in September.
Once again PARC is coordinating the amateur communications system for the Marathon on Sunday, October 6th, 2002. Operators wanting to volunteer should contact Pete, W7PR at 503-771-1773, or at W7PR@arrl.net, or Pat, KD7HDP@arrl.net. Please include you e-mail address and /or telephone number. Stations will need to have 2 Meter equipment.
