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you have probably noticed,commercial IEEE 802.11(hereinafter referred to as“802.11”)1 wireless network

equipment can now be purchased fromlocal office supply houses for less thanthe cost of a 1200 baud VHF terminalnode controller. Some adventurous Vir-ginia amateurs were amazed at how littlemoney and effort it took to establish areliable high-speed wireless data networkacross long distances—distances tradi-tionally associated with voice repeatersand 1200 baud packet radio. Using off-the-shelf components, these hams easilycreated a network operating at Internet-compatible speeds across a span of 34miles in a single hop. Yes, you read cor-rectly: that’s 34 miles!

Let’s take a closer look at what is go-ing on in this rural farming region—justa few hours’ drive from Washington, DC.

History and GeographyVirginia’s beautiful Shenandoah Val-

ley runs diagonally along the westernedge of the state. To the east are the sce-nic Blue Ridge Mountains, capped by thefamous Skyline Drive and the Blue RidgeParkway. To the west, the AlleghenyMountains form the border with WestVirginia. Nestled down in between thesetwo mountain ranges lies a 50 mile stretchof rolling hills, farmland and orchards thatprovide picture-postcard scenery.

IEEE 802.11 Experiments inVirginia’s Shenandoah Valley

As

1802.11 is a trademark of The Institute of Elec-trical and Electronics Engineers (IEEE)

The middle of the NationalRadio Quiet Zone is one of thelast places you’d expect tofind hams engaged in activewireless experimentation.David R. Fordham, KD9LA

Figure 1—All of the Amateur Radio activities described in this article occurred in theNational Radio Quiet Zone. Established in 1958 to minimize possible harmfulinterference to the National Radio Astronomy Observatory in Green Bank, WestVirginia, the Quiet Zone encompasses nearly 13,000 square miles near the stateborder between Virginia and West Virginia.

July 2005 35

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36 July 2005

Before shopping for802.11 gear, it helps toknow something abouthow commercial wire-less networks differfrom traditional hampacket networks.

A standard AX.25packet network startswith a user computerconnected via serialport to a TerminalNode Controller(TNC), which in turn isconnected to a radiotransceiver. The TNCtakes a data streamcoming out thecomputer’s serial port,divides it into 128-character chunks calledpackets, and thenmodulates the radiocarrier in a series of individuallynumbered transmissions correspond-ing to each packet.

The other end of a traditionalpacket circuit usually consists of oneof the following three types of sta-tions: (a) another ham with an identi-cal setup (computer, TNC and radio),or (b) an unmanned radio connectedto a TNC which receives packets andthen retransmits them on the samefrequency (called a digipeater), or (c)a device called a “node.”

The node consists of a radio anda specially programmed TNC. Thenode TNC receives packets, andrepeats them on the same frequencylike a digipeater. But the node alsohandles connections and performsother administrative overhead duties,resulting in more efficient use of theradio channel than a simpledigipeater.

And then there are dual-portnodes. A dual-port node receives apacket from one radio (generally onone band), and retransmits thatpacket on a different radio (generallyon another band). This is what isknown as a bridge. The dual-port

TNC and the radio. Thecard (along with its driversoftware) takes the data

stream from the com-puter, and breaks itinto packets, and theradio circuit on thecard transmits thepackets on the micro-wave band.

Two computers,each with an 802.11NIC card, can com-municate with eachother exactly like a

packet circuit. In the802.11 world, this iscalled “ad hoc” mode.

Another, more com-mon, 802.11 architec-ture uses a devicecalled an “accesspoint.” The access

point is akin to what ham packet op-erators call a “node.” In this architec-ture, the access point receives thepackets from one computer, andretransmits them like a digipeater,with the additional administrativeoverhead of connection management.

Most 802.11 access points, how-ever, also function like a dual-portnode, or “bridge.” Most of them havea built-in circuit that is capable ofmoving wireless packets off the radiofrequency and onto a wired Ethernetnetwork. How does it do this? Lookclosely at the packaging of your wire-less access point device. It probablyhas a four or five port “hub” built intoit. A hub is a device used on Ethernetnetworks to connect wired computerstogether. Most 802.11 access pointscombine a wireless digipeating nodewith an Ethernet hub, and a bridgecircuit between the two.

And to complete the picture, mostcommercial access points today alsoinclude a gateway circuit to move the802.11 and Ethernet packets ontothe Internet! These devices have aDSL or cable modem port in additionto their Ethernet ports! That is where

A typical IEEE 802.11 “access point.” This routing device combines a4-port hub, a bridge and a gateway circuit for the Internet interface. Italso includes an RF transceiver—a complete radio package to theInternet. All that’s needed is an Internet connection via a network cableor modem (cable or DSL) and an RF network interface card (NIC)plugged into a desk computer or laptop. Presto—wireless access!

TNC is taking a packet off one net-work (the first radio’s frequency) andmoving that packet to a second net-work (the second radio’s frequency).Note that both networks are using thesame AX.25 protocol.

Contrast the operation of a“bridge” with the operation of a “gate-way.” The term “gateway” refers to adevice that takes a packet off onenetwork, and moves it to a secondnetwork that uses an entirely differentprotocol and transmission medium.For example, you may be familiarwith gateway stations that acceptAX.25 1200-baud packets from aUHF radio and convert them toInternet (TCP/IP protocol) packets fortransmission over the worldwideInternet network. The Internet usesentirely different packet structures,routing schemes, and modulationmedium from AX.25. That is whatmakes the transfer device a “gate-way” rather than a bridge.

Now let’s relate this to 802.11networks. The simplest 802.11 deviceuses a network card (NIC) installed ina laptop or desktop computer. Thiscard performs the function of both a

IEEE 802.11 Jargon: “Routers, Gateways and Bridges...Oh My!”

Johnny Appleseed began his journeyacross America from one of these very or-chards. Abraham Lincoln’s father’s home-stead is here, along with the birthplace ofWoodrow Wilson. Jim Colter, the famousmountain man, was born here, as were threeother members of Lewis and Clark’s expe-dition. There is a large community of OldOrder Mennonites, who—like the Pennsyl-

vania Amish—still use horses and buggies.The Statler Brothers got their start here. TheShenandoah River, made famous in song,still sports a 19th century covered bridge.The river flows the full length of the valley,eventually emptying into the Potomac athistoric Harper’s Ferry.

Although the entire population of thevalley is smaller than the number of tour-

ists visiting Disney World on a typicalday, ham radio is well represented. Youwould think that on-the-air activity wouldbe limited, since most of the valley lieswell within the Radio Quiet Zone sur-rounding the National Radio AstronomyObservatory (see Figure 1). But the ob-servatory, located just over the mountainin Green Bank, West Virginia, has been

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July 2005 37

Figure A—A typical wireless network in Infrastructure mode.

the term “access point” derives.These boxes are used to provide“access points” to the Internet viaradio.

So you can see these little boxesare versatile devices. They canhandle packets in 802.11, Ethernetor TCP/IP formats. They listen to thevarious channels, and when anincoming packet is received, thepacket is switched (routed) to theproper outgoing channel based onthe packet’s destination address. Forthis reason, these devices are called“routers.”

A network that uses 802.11-equipped computers to communicateusing an access point device is said

to be operating in “infrastructure”mode. There are slight differences inhow the packets are handled be-tween “ad hoc” and “infrastructure”modes, but that is beyond the scopeof this article.

The experiments conducted byN4DSL, KG4PRR and K4DJG usedan Ethernet connection between thecomputer and access point on eachend of the radio circuit. The Ethernetpackets were converted to radiopackets by the access point. Theradio packets were then transmittedacross the valley, with the accesspoint handling the connection, ac-knowledgments and retries, exactlylike traditional packet radio.

more than happy to work with local ama-teurs. Rick Fisher, KE8DH, an NRAOscientist, leads an annual tour of the fa-cility just for hams. Wesley Sizemore (theinterference coordinator) bends overbackwards to allow as much ham radioactivity as possible, with the absoluteminimum of restrictions necessary to pro-tect their sensitive instruments and obser-

vations. He has done an admirable job.Indeed, judging by the activity on the hambands, you wouldn’t even know the QuietZone was there!

There are almost 600 licensed amateursin the valley. DX Hall of Famer and four-time DeSoto Cup winner Bob Eshleman,W4DR, got his start here. So did the ven-erable George Thurston, W4MLE (SK),

who was longtime SEC of ARRL’s North-ern Florida Section. Lifetime valley resi-dent Gerry Brunk, K4RBZ, is on theDXCC Honor Roll. Numerous nationalnets are called from the area, including thefamous Menno-Net.

The valley is home to numerous radioclubs and repeater associations. In thenorthern town of Winchester, you find theShenandoah Valley ARC. In the center isthe Massanutten ARA (MARA, namedafter the large mountain sitting smack inthe middle of the valley), and in the southis the Valley ARA (VARA). The clubs,especially MARA and VARA, cooperateclosely on many projects, including ajoint Field Day operation that consistentlyscores tops in the state and in the Top 10in their class nationally. All of this fromthe “Quiet Zone”!

Experimentation = FunValley hams have a rich tradition of ex-

perimentation. For such a rural and agri-cultural area, there is an astonishing amountof activity in new and unusual amateur tech-nologies. For example, the e-mail addressof former MARA President David Tanks,AD4TJ, is davidmoonbounce@aol.com.Cowles Andrus, K4EME, not only worksEME, but is also one of many hams activeon the orbiting satellites and meteor scat-ter. Vic Alger, KE4LKQ, has a satellite sta-tion that receives and filters data fromEMWIN (the Emergency ManagersWeather Information Network sponsored bythe National Weather Service) and postspictures from the weather satellites.

There is significant activity on PSK31,JT44 and other new digital modes. Thereis a repeater for fast-scan television, amonthly meeting for QRP homebrewers(surface mount, anyone?), and a lunchgroup that might best be called “HamRadio Aboard Recreational Vehicles.”

The W4PNT and KC4GXI repeatersare Echolink nodes, allowing users of2 meter and 70 cm transceivers to tiedirectly to the Internet using Voice OverInternet Protocol. At any given time youcan find more than a dozen active Auto-matic Position Reporting Stations, includ-ing several remote weather monitoringstations—and several hams operate APRSbicycle-mobile. The KB4OLM DX clus-ter is accessible from almost everywherein the valley. Yes, all of this is right herein the “Quiet Zone”!

The experimentation is not limited toradio, either. Wind generators and solarpanels provide power for packet-basedweather reporting stations atopShenandoah Mountain and the JamesMadison University campus. QST has evenfeatured an article by valley ham ChuckVogan, KD5KA, who crossed the country

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38 July 2005

working QRP from his motorcycle.So it was no surprise to anyone when

a local ham—who is not even old enoughto buy a beer!—proposed experimentingwith 802.11 gear on the 2.4 GHz micro-wave bands.

“To ‘B’ or Not to ‘B’—That is theQuestion”

While most kids his age were learningtheir state capitals, Jason Armentrout,N4DSL, was building computers in hisbedroom. He earned his Amateur Extralicense at age 15 and was one of the firsthams on PSK31. Now just barely 18 yearsold, he works professionally for a localcable company, designing, installing andconfiguring wired and wireless networks.

In early 2003, Jason became curiousabout the distances achievable with com-mercial 802.11 gear. The 802.11 equip-ment on the market today comes in threecommon flavors: 802.11a, 802.11b and802.11g. The differences among themare transparent for most users, and liemainly in the frequencies used andspeeds of transmission. 802.11b and802.11g advertise usable distances up toabout 300 feet.

The 802.11a equipment operates onthe 5 GHz band. The 802.11b and 802.11ggear is on the 2.4 GHz band, and of the11 channels available for operation in theUS, channels 1 through 6 overlap the 2.4GHz amateur band. This makes the “b”or “g” version much more suitable forexperimentation, especially for applica-tions that might result in signals outsidethe allowable parameters of the gear’sPart 15 certification.

The 802.11 equipment is designed toestablish Ethernet-like wireless networksat high (Internet useful) speeds. Most802.11 access point devices also are ca-pable of patching the wireless packetsinto the Internet (converting 802.11 pro-tocol packets to TCP/IP packets: a gate-way). See the sidebar, “IEEE 802.11Jargon: ‘Routers, Gateways and Bridges...Oh My!’” The question Jason asked was:Can 802.11 equipment be used at dis-tances that make it practical to establisha “valley-wide” high-speed TCP/IP-com-patible network? In other words, can a“Hinterland” network really cover such awide area using nothing more than thecheap off-the-shelf gear?

Jason conferred with amateurs at theclub meetings and the daily informallunches at the local Burger King. Helearned there are two ways that hams tra-ditionally go about experimenting withnew modes. The first is to build fromscratch, putting together components andbasic building blocks to form a communi-cations system. For microwaves today, this

Figure 2—K4DJGmounted the dishantenna to his trailerhitch, making for aconvenient “rover”microwave station atReddish Knob at thewestern end of the34 mile link.

Station 1Call sign: N4DSLLocation: Two-Mile Run Overlook on Skyline DriveCoordinates: N 38° 17.906' latitude, W 78° 38.914' longitudeElevation: 2770 feet ASL

Station 2Call sign: K4DJGLocation: Reddish KnobCoordinates: N 38° 27.946' latitude, W 79° 14.717' longitudeElevation: 4370 feet ASLBoth stations used a laptop computer equipped with a 10BaseT Ethernet

NIC adapter. The NIC was connected to a Linksys WET11 Ethernet wirelessbridge, configured in ad-hoc mode.

Physical Description of the Link Used in theInitial Experiments

means buying magnetrons, feedhorns,transverters, waveguides, exciters and soforth. This approach might result in a goodlong distance RF link. But the interfacebetween that RF link and today’s TCP/IP-based packets would require significantprotocol work, possibly even a custom-designed bridge or gateway. Jason wasinterested in building an operational net-work, not tinkering around with protocollayers.

The second way hams do things is to

adapt surplus or commercially availablegear for ham use. Being familiar withcommercial network gear, Jason asked thenext logical question: “Could 802.11 gearbe utilized to yield useful computer com-munication over distances in excess of thetypical radius of 250-300 feet?”

Eureka!On a cold Saturday morning in early

2003, Jason, Daryl Coffman, KG4PRR,and David Fordham, KD9LA, linked

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laptop computers using 802.11 equipmentacross a distance of about 3 miles. Usingsimple directional “barbecue grill” dishantennas, they drove from hilltop to hill-top, attempting to establish reliable datatransfer between their laptops from highspots farther and farther apart. These firstexperiments were characterized by mad-dening, unexplainable intermittent perfor-mance. Sometimes the link workedflawlessly, and suddenly it would just dis-appear. Hours and hours of testing anddiagnostics finally located the problem:a faulty connector on the coax feeding oneof the dishes!

Then early in 2004, the Eureka Momentarrived. After obtaining a set of amplifi-ers, Jason and Bob Van Fossen, K4DJG,set up stations on opposite sides of thevalley. Jason set up at an overlook onSkyline Drive in Shenandoah NationalPark. Bob drove to Reddish Knob inthe George Washington National Forest.They were able to establish a solid andpermanent connection using the setupshown in Figure 2 and the sidebar, “Physi-cal Description of the Link Used in theInitial Experiments.” The distance as cal-culated by a popular mapping program(Figure 3) was 34.08 miles!

Then for the icing on the cake: Takingthe amplifiers out of the circuit, they werestill able to establish a solid connection!And get this: The signal path ran directlyacross the city of Harrisonburg, two col-lege campuses, a hospital, a large shop-ping mall, and a commercial district, allof which are known to be using active802.11b wireless equipment!

Antennas on each end of the link were24 dB gain parabolic grid dishes (the so-called “barbecue grill antennas”). Thepower with the amplifiers turned on was800 mW (about 200 W ERP). Withoutthe amplifiers, the power was 30 mW, orabout 7.5 W ERP.

A surprising finding of the exercisewas that the data transfer rate was aboutthe same regardless of whether the ampswere in or out of the circuit. With theamps on, the signal strength was “100%”as determined by the indicators on thebridge. Without the amps, the signalstrength dropped to “65%.” The nominaldata rate remained at 1 Mbit/s regardlessof the status of the amps.

A disappointing surprise was the ac-tual data throughput rate. While the nomi-nal data rate (the rate at which the signalmodulation was pumping out the bits) was1 Mbps, the actual data transfer rate, asmeasured by an FTP file transfer, wasmore like 150 kbit/s. This is still fasterthan landline ISDN service, but a far cryfrom the nominal. What could account forthe low throughput?

Figure 3—Initial testingshowed that reliable con-nection paths could beachieved across the valleywithout power amplifi-cation, using onlydirectional antennas oneach end. The pink lineshows the radio signalpath, spanning over 34miles. The western end ofthe path was on ReddishKnob in the AlleghenyMountains. The easternend was at Two Mile Over-look on Skyline Drive inthe Shenandoah NationalPark. A mapping programsuch as Delorme’s TopoUSA can be helpful inevaluating and planningpossible microwave paths.

Figure 4—Diagram of the network that the MARA and VARA clubs set up for Field Day2004.

As mentioned above, the path crossednumerous other networks. Interferencefrom these networks (for example,carrier-sense delays) might be part of theproblem. But Jason proposed another ex-planation.

The IEEE 802.11 standard is designedfor transfer distances of 250 to 300 feet.The wait times and retry times are opti-mized for packet movement across such

short distances. At the speed of light, thedifference between 300 feet and 34 milesis significant. Jason postulated that thetime interval (taken for a packet to travelthe 34 mile distance, be received and de-coded at the destination, and the acknowl-edgment sent across the 34 mile returntrip) was so long, the originating stationhad already given up and was busy send-ing a retry.

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40 July 2005

By calculating the retry timing param-eters for the 802.11 protocol, and takinginto account the speed of radio signalsthrough air, Jason determined that themaximum practical distance using theprotocol was about 10-12 miles beforeyou begin to experience major problemswith the retry timing windows. What thismeans is, if you were using a path of only10-12 miles, the actual data throughputrate should increase tremendously. Andon a path of a mile or two, the through-put rate should approach the nominal1 Mbit/s signal rate (assuming no inter-ference, of course).

Even with the retry problems at 34miles, a throughput of 150 kbit/s is sig-nificantly better than a dial-up modem orISDN service, and over 100 times fasterthan 1200 bit/s packet. This means that802.11 equipment is a suitable approachfor a valley-wide Internet-compatible net-work.

Of course, if this equipment is beingused in ways that place its operation out-side the Part 15 certification parameters,care must be used to ensure compliancewith Part 97 rules. Operation of the equip-ment described with the 800 mW ampli-fiers is in clear violation of the Part 15rules, but the operation of the unamplifiedsystem clearly falls under the Part 15 andPart 2 rules as they have recently beenrewritten. In fact, the described systemcould operate as a Part 15 system by uti-lizing some of the 200 mW 802.11 hard-ware currently available from a numberof sources. The EIRP of such a systemwould be 50 W, which is lower than themaximum allowable power in a point-to-point link under Part 15.

If the system requires power in excessof the Part 15 limits, then Part 97 allowsamateurs to operate under a less-limitingrule structure. If the equipment is to beused in a Part 97 system, then the equip-ment must be configured to ensure usage

within the ham band (which means it mustoperate between channel 1 and channel6) and provisions must be made for the10-minute station identification. In addi-tion, content controls must be imple-mented to ensure that no commercialtransactions are carried by the network.But this type of experimentation is exactlywhat ham radio is all about.

One other consideration is avoidinginterference to AO-43 satellite users. Thiscan be accomplished by avoiding opera-tions on channel 1.

Into the WildernessPoint-to-point communication is good,

but networks are even better. Once it waslearned that long-distance connectionswere achievable, it was a simple matterto construct a multinode network and totie the system into the Internet. Okay, sowhy would you want to construct a long-

distance multinode network with Internetconnectivity? Two words: Field Day!

Each June, the MARA and VARAclubs work together and build a “city” inthe wilderness of the George WashingtonNational Forest. In a picturesque moun-tain meadow near Flagpole Knob on thewestern side of the valley, nearly 100hams and their families gather in tents andRVs, far from the interference of moderncivilization. To connect such a remotelocation to the Internet infrastructurewould provide the ultimate test for a long-distance computer network.

Figure 4 shows the basic layout of thenetwork. At the Field Day site, Jason firstestablished a standard 300-foot-radius802.11g wireless network, the kind foundin thousands of hotels, schools, and officebuildings. All of the computers used forField Day logging were equipped with yourplain vanilla, garden-variety 802.11 net-

Figure 5—The Field Day site in the mountain meadow featuredan IEEE 802.11b wireless network, connected to the dishantenna seen atop the mast in the center of the picture.

Figure 6—The IEEE 802.11b equipment at the Field Day site waspowered by solar panels located at the base of the mast. The router,designed for indoor use, had to be wrapped in plastic to protect itfrom the morning dew. A valley inside-joke is that “It never rains atField Day, although sometimes we have a heavy dew.”

Figure 7—The relay station featured two dish antennas, one pointed at themountaintop, the other at the tower located in the K4RBZ’s backyard. Both disheswere connected to a single IEEE 802.11b router.

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Figure 8—Daryl,KG4PRR,installing thedish antenna atthe home ofK4RBZ.

work cards. Additionally, the mountaintopnetwork served any personal 802.11-equipped laptops within the 300-footomnidirectional range of the access point.Bryan Fordham, KG4JOE, even used thenetwork with his Toshiba handheld PDA.

One of the nodes on this network wasan access point, connected to the direc-tional antenna in the middle of the FieldDay site (see Figures 5 and 6). This di-rectional antenna was aimed at a relaystation 17 miles away at a hilltop repeatersite down in the valley (Figure 7). Sig-nals from the mountaintop network des-tined for the Internet traveled 17 milesdown this path to the valley.

The relay station was an 802.11 routerconnected to two directional antennas.One of these was pointed at themountaintop meadow Field Day site, andthe other pointed to a dish located fourmiles away on a tower at the home ofGerry, K4RBZ (Figure 8).

The dish at K4RBZ was connected toa third 802.11 access point, which in turnwas wired to a standard commercial cablemodem on the Internet infrastructure(Figure 9). Thus, the mountaintop wilder-ness computers were connected via thedish antenna to the relay station, toGerry’s cable modem, using off-the-shelfcomponents.

Talk about experimentation with practi-cal application! It was great to sit in yourhammock enjoying the cool mountainbreeze of a forest clearing, notebook com-puter in your lap, checking your e-mail andbrowsing the Web while watching thewhite-tail deer saunter through the wild-flowers! One of the most important uses ofthe Internet connections was checking thelatest weather radar images for approach-ing thunderstorms. The network was alsoused to verify the latest elements for the

orbiting space station, and the Field Dayoperation made contact with N1ISS!

And remember, all of this was takingplace in the Radio Quiet Zone!

The Next Step?After the initial tests were completed,

the group located an 802.11 card that al-lows changes to the retry time parameter.With the new cards, they successfullypassed the 56-mile mark with great datatransfer rates. A 72-mile path is next.

These experiments demonstrate thesuitability of using commercial 802.11equipment for relatively high-speedpoint-to-point and network data commu-nication across relatively long distances.But what about mobile operation? If reli-able connections can be made from oneside of the valley to the other, and fromthe peaks to the valleys, can a series ofthese dishes be linked together to providea blanket of coverage sufficient to allowmobile operation?

At a distance of 12 miles, a dish witha 10º beamwidth will cover a swath of realestate more than 2 miles wide. An arrayof six or eight dishes located on oneside of the valley might be able to offerusable links to most of the hams inRockingham County. By using a secondarray for Augusta County, and linking thearrays together, a truly wide area high-speed TCP/IP compatible network shouldbe possible. And because each of thedishes would cover a smaller area, thestation-to-station interference would bereduced, somewhat akin to the cellulartelephone networks.

These experiments used directionalantennas on both ends of the link. Whatis the practical usable distance when oneof the stations uses a directional dish andthe other station (perhaps a mobile) is

Figure 9—The final antenna was connectedto another IEEE 802.11 access point, whichwas wired to K4RBZ’s cable modem.N4DSL is an employee of Adelphia CableCompany, which provided the connectionto the Internet infrastructure. That’s K4DJGin the background.

using an omnidirectional antenna? Acharacteristic of the 802.11 protocol isthat if the signal strength decreases, reli-able communications can still continue,albeit at a slower rate. This makes usingtraditional signal-strength calculationsand tables problematic.

Reducing the distance from 34 milesto 12 miles will increase throughput. Butreplacement of one of the dish (gain) an-tennas with an omnidirectional antennafor mobile use will reduce signal strength,decreasing throughput. What will thetrade-off ratio be? Will using a bigger dish(higher gain) on one end of the link com-pensate? What effect will the amplifiershave if put back into the circuit?

These questions will be giving Jasonand the Shenandoah Valley hams an ex-cuse to continue the fun through the com-ing months. In the meantime, the entirecrew here in the Quiet Zone is interestedin corresponding with other hams who areexperimenting in this area. If you are us-ing 802.11 gear on the ham bands in waysnot covered by the Part 15 rules, pleasecontact Jason at n4dsl@atrs.com.

David R. Fordham, KD9LA, has been a hamsince 1974. He holds a CPA, CMA and PhD,and is currently PBGH Faculty Fellow andProfessor of Information Technology at JamesMadison University. He is trustee of the JMUWireless Experimenters station WN4JMU,and is past president of the Massanutten Ama-teur Radio Association (MARA). He edits andpublishes the Monitor, the joint monthly news-letter of MARA and the Valley ARA. You canreach him at 131 Wayside Dr, Weyers Cave,VA 24486; fordhadr@jmu.edu.

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