It is most convenient to use at least a 10 foot tape measure. Tape measure yagis so named because the elements are made from a metal measuring tape have become very popular in the last few years, especially for rdf and emcom work, because theyre simple to make, inexpensive, lightweight. Dual purpose, dual boom portable tape measure yagi for 2 meters and 70 cm. Hurst amateur radio club uhf tape measure yagi foxhunt. Tape elements cut the 4 lengths of tape measure steel carefully to length, using a sharp pair of scissors dont tell the xyl. Measure and cut the four lengths you will need for this antenna cutting chart below. The 2 meter band tape measure beam antenna is a 3 element yagi with about 7. The tape measure antenna is a simple, handheld 2 meter yagi. A tape measure vertical antenna acadiana amateur radio. The factory defaults have been inadvertently changed, reset factory defaults all. Using the nut that came with the bnc connector, affix the connector to the bicycle hand grip. T yagi antenna design text and graphic from wikipedia.
Pass the coax through the hole, leaving the bnc connectors base in the hole. Tuning for resonance 4 elements twin yagi and adding the phasing. Cheap and light portable 2m yagi 9 db gain for less than 9 pounds build in march 2006 by maik, m0run in february 2006 i took part in my first ever foxhunt and there i had the idea to build this antenna. Ok, after you picked out your wire and gotten it ready to use, its time to measure it all out. The driven element is made up of two pieces, so cut two pieces that are 17 34 inches long.
Forming the holes in the tape is a breeze if you have a leather hole punch tool. Hurst amateur radio club uhf tape measure yagi foxhunt antenna 1 2 1 1 4 1 8 hairpin match 12 or 14 awg solid copper wire form to shape sand away paint solder coax and hairpin match to driven element on tape ends to bare metal view a 11 16 spacing 5 turns rg58 coax and wrap with tape center freq. They usually come in lengths from 6 feet to 35 feet long. One piece will be 41 38 inch and the second will be 35 18 inch. With a gain of approx 7dbd it is the equivalent of multiplying your transmit output power by 5 compared to a half wave dipole. First, well reduce cost and then well add oscar sat ellite mode j capacity. Each half is held in place by a screw and a wedge fit between the dowel and the pvc pipe. Build the 3 x 5 elements 2m70cm dualband yagi dw1zws.
This photo also shows a tape measure alongside the antenna. The formula and basics of yagi antenna calculator are also explained with example. I had at first thought to just drill extra holes in the existlng single. Cheap yagi for 70 cm build this cheap and easy satellite downlink antenna by richard f. A yagi has nearly perfect tuning when a reflector is selfresonant right on the tx frequency up to slightly below the tx frequency. Driven element is excited directly via feedline, all other elements excited parasitically. Jan 18, 2015 it was a particularly slow afternoon at work that day, so i scrounged up some scrap parts and made and antenna. The scouts measured and cut all tape measure elements, prepped all components, tinned and soldered the driven element connections and pieced together. You obviously do not need a 50 foot tape measure to measure the wire like shown. A tape measure is a roll of metal tape with measurement markings on and is used for measuring.
Camden county amateur radio society georgia ccars inc. This link is listed in our web site directory since sunday jan 26 2014, and till today tape measure yagi antenna has been followed for a total of 625 times. This lightweight antenna is perfect to use for fox hunts or as a portable directional antenna for public service events. This design exhibits a very clean pattern and is perfect for rdf use. During my tests i attached the case of a tape measure to one of the top sections of a 10m fibre glass fishing pole. The haul down line provides a quick, easytosee reference of the antennas different tuning lengths and to retrieve the an. This antenna is designed for twometer operations, which, for a newbie ham operator, is one of the bands available under the technician license in the us. Final tuning before final installation of the antenna, temporarily set it up in a clear area at least 6 feet above the ground. The dx engineering hms hairpin matching systems is a convenient way to match the feedpoint impedance of a yagi antenna with coaxial cable. A simple 4 element 2 meter yagi made from coathangers or other common materials by pete rimmel n8pr.
Disassemble the tape measure by pulling the tape out of the case. That was until i made a qso with k1maz nick while he was doing a sota activation. Now, remove the masking tape keeping the system inside the case, and reattach the top cover with the screwdriver. They can be made using various materials and in varous sizes. For the most part they all seem to roughly the same. Apr 11, 2005 so heres how to tune a computer generated new prototype yagi the first time out.
But i just wanted it to fold up enough to get it in and out of a car without hanging up on the door. First measure and cut some wire or rod to the dimensions we need. While the hairpin has been popular with radio operators for years, this model improves on the classic design by using adjustable rods to quickly match yagi. The spring will recoil into the case and the tape will be ready for trimming. First, loosen the set screw with the allen key provided and make a slight adjustment to. The tapemeasure antenna is a simple, handheld 2 meter yagi. Upper shroud tension check the upper shroud tension using the pt1 loos gauge. Electrical designs are optimized using the latest in computer aided technology.
If, after completing this guide, your tape measure still doesnt work properly, consider purchasing a new one or upgrading to a laser tape measure for reading at a distance. I modeled th1s with eznec and saw that it is a poor idea. For completeness this is not the only diy tape measure yagi on instructables so also check out. Adjust your headstay so that your rake is between 8. How to build a 70cm tape measure yagi antenna youtube. Tape measure yagis so named because the elements are made from a metal measuring tape have become very popular in the last few years, especially for rdf and emcom work, because theyre simple to make, inexpensive, lightweight, portable, and easily stored. The wb2hol tape measure beam is one of the standards for transmitter hunting. Steps to tune a yagi from scratch print this out the am forum. Here are the directions for building a tape measure yagi. This antenna is designed for amateur band frequency for both vhf 2m and uhf 70cm. The antenna is out of calibration, perform the calibration as described in the manual. Qrp to the iss doug cook, kd5pdn contacting the international space station with a few watts and a shoestring budget antenna. If you followed directions, you should be able to adjust this to very nearly 1. In this article well take that design two steps farther.
Jan 30, 2012 a bit of advice is to measure from the tip of the drill bit 14. Tape measures are commonly used in construction, architecture, building, home projects, crafts, and woodworking. Simply download the yagi cad program and put the tape measure beam design file in the same directory. Yagi in the 1920s did not receive full acclaim in the united states until 1928. If the distance from your antenna to your radio is greater than 15 feet, use a low. I had at first thought to just drill extra holes in the existing single. Hurst amateur radio club uhf tape measure yagi foxhunt antenna. Mark and cut tape measure using tin snips to the proper lengths as shown on blue print 6. This will be the director of the antenna and will attach to the front of the antenna. I folding for storage a particularly handy feature of this design is the dual boom. You will need to secure a suitably sized washer to the anvil to punch through the tape.
Testing a tape measure yagi antenna for 2 metres youtube. Yagi troubleshooting guide 1 of 6 the most common problems read this first. So what could be done is feed the reflector like a dipole, tune the reflector for resonance at the lowest expected operating frequency in each band, and then short the reflector feedpoint and add the driven element. The radiating length at present is 58 the antenna will radiate from the base of the previous loading coil to the tip of the stainless steel whip, and the length will provide plenty of extra length for tuning vswr. The beam as provided in the kit is good for 2m but it has also been successfully scaled for use on other frequencies including 121. Jul 19, 2015 dual band tape measure yagi antenna july 19, 2015 amateur satellite, antennas, ham radio amateur radio, antenna, ham radio, satellite, saudisat 1c, so50, yagi michael while i wait for my arrow antenna to arrive, i thought i would experiment and build a dual band tape measure yagi since i already had most of the parts on hand. The tape measure antenna is a home brew 2 meter antenna made out of pvc pipe and a steel tape measure. Also, it makes an excellent school, club or boy scout project. I have a few questions about tape measure antennas.
I have seen tape measure yagi builds where people roll up the elements and velcro around the outside, and that would make it even more compact. To scale this antenna for any other vhfuhf frequency, read the arrl article. Once you have cut the tape measure to length, put vinyl tape on. Checking the swr response of the 4 element yagi before delivery. And connected to the steel tape by means of a nut, bolt and solder tag at the start of the tape. After seeing a lot of articles written about making a three element yagi using pvc and a tape measure, i was interested but not excited about it. Completing the package for the gokit are a pair of lines to haul the tape measure up and down, and a set of ground a tape measure vertical antenna feed the end of the tape and tune for minimum swr by hauling the housing up and down.
Apply electrical tape or use a silicon compound to weatherproof the solder joints. Element lengthsdiameters and element spacing determine antenna behavior. Uda, are also commonly referred to as beam antennas or high. The main category is ham radio directional yagi antennas that is about yagi antennas for ham radio use, manufacturers, plans and design. I heard a 2m tape measure yagi is something that can be made cheaply plus i just want to make an antenna and see what that is about. I modeled this with eznec and saw that it is a poor idea. Build your own 2m70cm 3 elements vhf by 5 elements uhf yagi antenna with excellent gain for both vhf and uhf operation. Mark also suggested i bake the yagi in a low temp oven for a day or so to drive all moisture out of the wooden boom, then give it a coat of clear lacquer. These are the reflector and director elements for your yagi. It trades a bit of forward gain in exchange for a very deep. Jan 02, 2018 a simple tape measure yagi for 2 metres 144 mhz. The antenna is useful especially if you want a portable antenna for back packing etc.
If you feel uneasy about drilling the element, you should have a couple of inches of scrap rod that you can test both drilling and tapping on. Some are based on lookup tables, some completely hide their algorithms. A complete kit is also available that includes the tape measure beam with an assembled and tested offset. There are many sizes for young students, called fractional sizes up to full size for taller kids and adults. You dont want to use anything much thicker, it will change the tuning of the antenna. My take on the wb2hol tape measure yagi radioreference. The calculators for other antenna types such as parabolic,horn,dipole and patch are also mentioned. Virtually no ham antenna article today lists all the materials, tools and speci. Once you have cut the tape measure to length, put vinyl tape. Your new laird yagi antenna has been designed for accuracy, durability and value. Cheap yagi for 70 cm build this cheap and easy satellite. Chamfer off the corners at the cut ends for safety. Attach a tape measure to your main halyard and hoist and position it in the halyard lock.
John portune, w6nbc any hams have made 2 meter lape hunting. Figure 4 shows the way to measure the wire the best. Talk to satellites and the iss with ham radio ham radio crash course duration. On the two driven element pieces, sand or grind away the paint from one corner. It contains formulas you can use to calculate element lengths and spacing, as well as boom length. Tape measure antenna i began my antenna using the design on joe leggios, wb2hol, website theleggios. There is usually a label inside the instrument that includes the size. You will then be able to experiment with the design. Following a design published online by joseph leggio, wb2hol, pvc pipe segments and hairpin match wires were precut to length. Simply rotate the tape till the tab of the spring can be slid through the slot in the tape.
Measure and cut the four lengths you will need for this antenna cutting chart. I have looked at many different plans on the internet. This antenna is designed for twometer operations, which, for a newbie ham operator, is one of the bands available under the technician license in. Usually the tape is yellow and rolled in a plastic case. Tuning to make tuning the antenna easier over a wide range of frequencies, i clamped fig 2solder the coaxial cable to the driven element stubs as shown. Pass the coax through the hole, leaving the bnc connectors. Tape measure beam work the oscar ham satellites or go transmitter hunting with this inexpensive portable dual band handheld tape measure yagi. Simply twist the tape so it disconnects from the spring. The tape is cut in the center and there is no electrical connectivity between the two halves of the driven element. If you pull the tape past its end, youll find that its connected to a spring. A t match tuning peculiarity by dick knadle, k2riw edited 81206 it is a common misconception that adjusting the arm lengths of a t match will change only the resistive portion of the impedance match to the driven element of a yagi.
The vertical antenna plays out from the tape measure as it is hauled up with a line tossed over a limb. Apply rf power to the antenna and check for low vswr while performing each of the following steps. A simple 4 element 2 meter yagi made from coathangers or. Drill or cut a small hole in to the bicycle hand grip so that the bnc connector will fit. This page covers 3 element yagi antenna calculator. Building a 2element tape measure yagi during the march 22, 2018 meeting, dave joseph w1amx discussed how to construct a simple 2element directionfinding yagi for 2 meters. Current only resets the band segment you are currently on. It will be listed as a fraction, like 14, 12, 34, or 44, which is just a strange way of saying full size. Tape measure beam optimized for radio direction finding joe leggio wb2hol description this antenna evolved during my search for a beam with a really great fronttoback ratio to use in hidden transmitter hunts. That is the tuning mechanism for the antenna, and both the length of the gamma rod and the position of the shorting strap from rod to driven element are critical. Measure your rake to the intersection of the deck and the center of the transom. It is quite possible, that other calculators deliver slightly different results. The foxhunting receiver rox2a we used had a simple 3 element yagi with elements made of steel tape measure. To put tapes in the right spots, you need to know what size your violin is.