2m and 70cm coaxial dual band antenna pdf

Made up from two half wave sections separated by a coaxial phasing coil. Looking to get a highly recommended nagoya na771 37cm dual band 2m70cm handheld antenna for my baofeng uv5r. Why diamond misrepresents their antenna gain is anyones guess. Theory predicts that the losses are very small on any antenna when the swr is. Resources listed under j pole category belongs to antennas main collection, and get. The half wave 2m version of the flower pot antenna is easily modified to a dual band antenna for operation on a band that is the approximate third harmonic of the fundamental resonance. Pg1ns ham radio site 70cm projects directional antennas.

Comet gp3 dualband vhfuhf base vertical antennas gp3. Don murray w9ve building a dual band antenna mentorfest 102304 2 rubber ducks are kinda like rubber chickens rubber duck nearly an isotropic source, but not as good victims head absorbs some of the rf maybe that explains a. Aluminium foil for 70cm section antenna is a vertical collinear design. Your choice can be a leopack antenna system distributed by amsat. No endorsement may be inferred from the mere listing of a url or link. Dualband 2m440mhz base antenna the gp9 is the highest gain, dualband fixed station antenna available from comet.

The diamond x700h 2m70cm fixed station vertical, x700h diamond 2m70cm fixed station vertical this model is made of fibre glass construction, pretuned and fully weatherproofed. Since my article on simple wideband yagis appeared in september ar i have had a number of people contact me advising that it would be better to use the grey electrical conduit rather than the orange version i did. Uhf yagi is based on dl6uw yagi antennas designformula. Dual band mobile antenna conceived to cover the radioamateur band of 2m 70cm, without tuning adjustments. It has been suggested that i should try a better antenna with my baofeng before i buy more radio so im willing to give it a shot. Build the antenna using any tips and tricks that you can apply to the construction to make the vertical. A tri band antenna for 2 meters, 220 mhz, and 70cm antenna without radials by.

It has been made of high quality materials to get the best efficiency. It requires no radials, is totally weather protected, and only 5. Can the popular dbj1 dual band base antenna be adapted to also work at. This 50ohm impedance antenna, when fed with 25100w of ssb rf at 435mhz, makes reaching amateur satellites such as ao40 and ao10 a snap. For someone like me who doesnt want to invest in a large yagi array and a big rotator to turn it, thoughts turn to omnidirectional, horizontally polarised antennas. Comet gp9 dualband vhfuhf base vertical antennas provide very high gain on the 2meter and 70centimeter bands.

The whip is of black chromed stainless steel and all its metallic components are of brass to guarantee the maximum strength. Comet gp9 dualband vhfuhf base vertical antennas gp9. Particularly used in a city or area where the repeater sites are generally higher than the mobile station due to the pattern having an uptilt. However, if the only repeater you intend to use from your home is a 2m machine, and you have no interest in other vhfuhf band operations, then a single band vhf antenna may be your. Diamond antenna dualband ht antennas offer a wide range of features to choose from for your handheld transceiver or scanner. If larger coaxial figure 3the 2 meter jpole modified for both vhf and uhf operation. Amateur radio trends lean towards a dualband antenna with 2m and. Electronics free delivery possible on eligible purchases. Dbj2 dual band roll up antenna available in ham 144148 mhz and 440450 mhz or commercial 152157 mhz. Being very happy with the new antenna and having 2m of pvc pipe left over, the next day i decided to build another one, this time with the foil sheath added so it could be used on 70cm as well. Matching is excellent on all three bands and can be tuned independently.

Whether you need a replacement antenna or want to improve your hts. Repurposing rebanding a cellularpcs antenna into a dual band vhf uhf antenna. This is an excellent performing jpole type antenna. Works great with rtlsdr recievers and baofeng portable radios. A wide variety of dual band antenna 2m 70cm options are available to you, there are 176 suppliers who sells dual band antenna 2m 70cm on, mainly located in asia. In my page you will find several details of manufacture, additional. If my math is correct this is about a halfwavelength antenna for 70cm, but doesnt seem to correlate to anything for 2m. Ed fongs dual band vhfuhf antenna part ii duration. Be sure to use 50ohms coaxial cable to feed the antenna. This antenna is based on vk2zios flower pot antenna. Dualband 3x5 cross yagi 145mhz 435mhz mounting and. If you desire the absolute maximum coverage area, this is the antenna to choose.

The smaller diameter sections are the inner conductor of the coax with its. The theory is not necessary for this antenna to work, so those who can not wait and immediately. A vhfuhf dualband jpole searching for an inexpensive, highperformance dualband base antenna for vhf and uhf. This antenna can be rolled up and used for portable operating or placed inside a. Discussion in vhfuhf 50mhz and beyond started by mrbombastic, feb 20. Building jpole amateur radio antennas category is a curation of 86 web resources on, j pole antenna for 6 meters, the jpole antenna revisited yet again, the copper cactus jpole.

Boost your signal with our selection of vhfuhf beam antennas. Most terrestrial dx activity on 144mhz uses ssb, cw or digital modes and horizontal antennas. D o you need to operate 145mhz and 433mhz transceivers simultaneously with one dualband antenna. The top countries of suppliers are india, china, and taiwan, china, from which the percentage of dual band antenna 2m 70cm supply is 1%, 93%, and 3% respectively. Pg1ns ham radio site 2m projects omnidirectional antennas. X200a 2m70cm dual band high performance gain base station antenna diamond antenna products are distributed by rf parts company 435 s. Buy diamond original srh779 telescoping 2m70cm handheld antenna sma. Comet gp3 dual band vhfuhf base vertical antennas provide very good gain on the 2meter and 70centimeter bands. Stepbystep instructions with photos can be seen below, following the project description and safety disclaimer. This is the actual measurements of the cross yagi antenna ive used for satellite work, though the inline version of this yagi in which the vhf and uhf side are mounted inline but on the opposite side of the boom will also work for satellite communication.

It appears the engineers and product teams did not share much information back in the day of its design. To construct this antenna you will need a length of at least cm rg58 coax. Dbj1 dual band base antenna available in ham 144148 mhz and 440450 mhz or. This handy box lets you use one feed line for both vhf and uhf energy, simultaneously. Items used are items from the dollar box at a hamfest tailgate and everyday hardware. We offer a huge selection of yagi antennas, including crosspolarized and circularly polarized, from top brands like m2 antennas, cushcraft, mfj, and diamond antenna. It only took it only took around 90 minutes now that i knew what i was doing, including mounting it on the roof. Be sure to use 50ohm coaxial cable to feed the antenna. This easy to build dual band vhfuhf antenna makes a great project for the new ham that. Dualband 2m and 70cm yagi antenna pa1444321932cb two.

I invented a similar system, but completely made of rg58 coax. When sliding the antenna into the pvc tubing, i found no need to anchor the antenna once it was inside. But rather than a conventional coaxial dipole side bar right, this coaxial takes. My operation is mainly working locals, the occasional. This antenna meets the demands set by aresraces group for ruggedness, easy deployment, and performance. Diy simple dipole antenna for vhf and uhf bands 2m and 70cm.

I highly recommend a dual band radio and antenna for the new technician class ham as a starter station, most typically the 2m440 combo with an antenna to match. The radiation pattern is directed to the horizon omnidirectionally around the antenna. My antenna making skills are about on the twinlead jpole and simple groundplane level so im not sure how well thi will turn out. Dualband portable noground plane antenna qrz forums. Halfwave flower pot antenna 2m or 2m70cm dual band. Showing the antenna i purchased from ed fong for my 2m, 70cm operation. The cp22e is a very impressive antenna and 5 dbi in a nine foot 2m antenna is a design win. To construct the antenna, first select a suitable length of grey 25mm conduit as a minimum 1m but if you make it longer, you will have more room below the coil to. Very short yet efficient antenna, mainly used in metropolitan areas where extended range is not critical. The portable or base 2m70cm copper pipe j antenna by. I wasnt stating that this antenna would do exactly what was shown in the model. View and download diamond antenna x300na manual online. This is my revised base 2m70cm copperpipe j, a howto diy with an optional method to make a portable dualband j for hotel travelers, restricted apartment dwellers, or for limited balconypatio use.

The diagram below shows the basic arrangement of the 2m halfwave version of the antenna. Vhf and uhf antenna systems 1821 fig23these drawings illustrate the dimensions for the 144mhz groundplane antenna. A tri band antenna for 2 meters, 220 mhz, and 70cm antenna. I cant seem to find a simple dual band yagi made of cheap, easily sourced materials. But recently at a parade it struck me that a more versatile design might be a classical gentlemans walkingstick antenna. A simple 2 m 70 cm vertical dipole antenna this easy to build dual band vhfuhf antenna makes a great project for the new ham that is ready to get on the 2 meter and 70 centimeter amateur radio bands.

Copper dual band super jpole antenna by ka0nan, april 1993. Simple wideband yagis for 2m and 70cm errata and extra. Compact and effective 2m70cm dual band antenna for satellite operation building the uhf cheap yagi for satellite communication station buy motorized crossed yagi antennas solution is the best solution but certainly not the cheaper. Figure 2this eznec plot shows the difference in the radiation patterns between a vertical halfwave radiator operated at its fundamental 146. Simple wideband yagis for 2m and 70cm errata and extra pictures. A lowloss vhfuhf diplexer by pavel zanek, ok1dnz why use two lengths of expensive feed line when one will do. This is also a nice ham project, een small antenna for 2m and 70cm, after using it you can. In my previous posts, all i was trying to do was state that i had used an alternate modeling software pkg and come up with the same basic results. It may be much eaiser for some of you to start at the center of the antenna and work toward the shack end of the coax in the second method above. Whether youre operating on 2 meters or you work in the 1.