One wire of the feedline connects to the base of the antenna, and the other connects to ground. This counterpoise usually consists of a system of radial wires placed either on the ground or elevated above ground. Knowing how to ground or earth an antenna system can be a key factor in the operation of some antennas. A copy of the faa advisory circular can be obtained at. So not only do i have that reader to thank for prompting me to inspect and correct my current antenna grounding system, but they potentially saved me a world of trouble if lightning were ever to strike near my house. The ground system consists of a cable connected to a copper rod driven several feet into the earth. Cm7777hd, cm7777, cm7778 what is a distribution amplifier and do i need one. Article 810 refers to article 250, grounding and bonding, so i also will discuss its associated requirements. Grounding electrode system and grounding electrode conductor part iii znec 250. History of lightning protection system design in tactical sstems many older communication systems do not have lightning protection incorporated into their design. Lightening not only kills radios but can start house fires.
Capacitive grounding may only reradiate these interfering signals somewhere else aboard the boat. This surprised me until i had an email conversation with joe reisert, w1jr, the original designer. Antenna system bonding and grounding requirements in. Finally, it is best to develop an entirely separate grounding system for lightning. If the antenna system has bad common mode current problems, caused by a faulty antenna or feed line design or installation, a ground can help reduce common mode noise reaching the antenna. A lightning arrestor consists of a spark gap that will arc when more than a few hundred volts exists across the points. Knowing how to ground an antenna properly can make significant improvements to its performance, whereas a poor ground or earth connection can mean that its performance is greatly impaired. How much signal do i lose going through a splitter. Ieee industry applications society atlanta chapter january 19, 2010 meeting 2. Vertical antenna ground systems at hf rudy severns n6lf introduction a key factor in determining the radiation efficiency of verticals is the power loss in the soil around 1 the antenna. The first thing to know is that there are three functions served by grounding in ham shacks. Gps antenna installation guidelines general information installations must be made by qualified personnel, and in accordance with federal regulations. Site considerations for equipment installation, grounding.
The main category is grounding systems and techniques that is about grounding systems and techniques. This is required only for certain types of antennas ones which require current flow to ground to complete the antenna circuit. Grounding vhf base station antenna amateur radio stack. Power, grounding, bonding, and audio for ham radio safety, hum, buzz, and rfi. The grounding system has a plurality of fractional wavelength electrically conductive members joined together and connected to the electrical ground of the transmitter associated with the antenna. Guide for grounding an antenna system guide for grounding an antenna system electrical question. A closer look at vertical antennas with elevated ground systems rudy severns n6lf. The tem leadin refers to any cable or conductor from the antenna system including coaxial cables, waveguides, rotator control cables, and powering conductors and cables for mast or towermounted amplifiers and other outdoor electronics associated with the antenna system. Communication site building design and installation 31 3. Its not that hard to develop your own sideband rf ground system in just about a days time, and you may even find that most of the rf ground system is already installed so you have little to do but to tie everything together with copper foil. Experimental data are given which show that an eighthwave antenna is practically as efficient as a quarterwave antenna. The important thing is to eliminate commonmode currents in your antenna system, perhaps with a balun.
This is not an indepth publication but simply a general guide on installing and using steppir verticals. Please consult the nec, a local licensed electrician. Amateur radio station grounding rcc mar 2007 lane giard, n7zxp this article comes from don young, n7dy, which was in the wenatchee radio club news letter. The us army signal corps recently reported on the results of improved grounding techniques for mobile field tactical radio stations. According to nec rules the antenna can be grounded to a water pipe but the water pipe must enter the earth within 5 feet of where the ground connection is made on the pipe.
If the antenna is unbalanced, a radial system or counterpoise is necessary for operation. Grounding systems and techniques category is a curation of 38 web resources on, safe,effective grounding, notes on ground systems, grounding and reducing noise. This source of overvoltage is, in a properly grounded system, provided with an alternative path around the electrical system of your home or workplace by intentionally connecting the system to the earth. Does not help with rfi does not make an antenna work better. Maximumgain radial ground systems for vertical antennas al christman, k3lc table i optimum number and length of radials for a vertical antenna on 40 meters 7. Assuming you placed your antenna outdoors, you may be lucky enough to find an outdoor water faucet near the end of. Ground impedance, and earth surface potentials of a ground system to address issues related to large grounding systems or systems in congested areas. Antenna system grounding by larry d barr, k5wlf intro. As a result, if the ground sucks, the antenna will also. In reality it is very difficult to get an antenna rf grounding system that is lossless and it is accordingly difficult to fully realise this gain.
A complete grounding system for the antenna, towers. Vertical antennas can have radials mounted on or below the surface of the actual ground. Ground metal enclosures and exposed metal parts of electrical instruments in accordance with osha rules and regulations as specified in design safety standards for electrical systems, 29 cfr, part 1910, subpart s, dated. I would remove and replace the antenna coax connectors from both the transmitter box the. I inspected the wiring of my antenna with the intention of doing a write up on how it was grounded. Proper antenna grounding posted in technical discussion. I will be installing a gable antenna mount which has a 6 extender pole on my single story home. About antenna grounding system the resource is currently listed in in a single category. Improvements and changes to this manual necessitated by typographical errors, inaccuracies of. How to install an earth grounding and bond for communication antenna. No place on earth, that i know of, is completely free of the threat of lightning. Power, grounding, bonding, and audio for ham radio safety, hum, buzz, and rfi jim brown k9yc. Tv antenna installation guidelines for better tv reception. Simple antennas and good grounds university of hawaii.
I will discuss the nec bonding and grounding requirements that apply to radio telescope. This pipe then would have to be underground at least 3 feet to be effective. The best way to create a good ground connection is to use a metal cold water pipe. Spark gap, gas discharge to ground system ground all antenna support structures modify lc lowlow passpass filter,filter, longlong coaxcoax runrun block and shunt inductor toto groundground systemsystem forfor staticstatic andand pulsepulse spark gap to ground system for pulse and quench. On installations where the electrical utility system is owned by a private entity, consult with the private system owner. All communications systems need antenna towers, which naturally invite lightning strikes that can cause damage to a centers sensitive equipment. View grounding accessories more about tv antenna grounding. If you find that you have resistance, youll need to determine where along the line the circuit is open. Review the lightning protection system record drawings on each facility at least. Nov 04, 2017 this is for television antennas not ham radio, do not follow instructions for radio grounding. Site considerations for equipment installation, grounding, and wiring manual d301452x012 october 2019 ii device safety considerations reading these instructions before operating the device, read these instructions carefully and understand their safety implications. Tests of groundscreens show them to be ofnoimportance whenadequate ground. With the exception of the vertical dipole, a dipole on its end, vertical antennas are only half there. After antennas, station grounding is probably the most discussed subject in amateur radio and it is also the one replete with the most misconceptions.
Now, as i was replacing an existing outdoor antenna, i simply hooked the antenna up to the already grounded coaxial cable coming off the roof. Once youve done that, there wont be any need to ground the antenna for performance. Since a halfwave dipole has a radiation resistance of 73 ohms, a quarterwave monopole will have a radiation resistance of about 36. First and foremost, grounding is for the safety of your family, home, and ham equipment. Digital ota tv now offers more channels all with outstanding picture and sound quality. Steps i would take to check and improve your system. The grounding requirements for antenna cables are con tained in 810. Grounding systems and techniques category is a curation of 38 web resources on, notes on ground systems, grounding and reducing noise, verticals. Power, grounding, bonding, and audio for ham radio safety. Proper grounding of the antenna mast and leadin cables is somewhat effective in protecting receiving equipment from. The antenna was designed to work without a ground system and although the antenna is.
This assumes that there are no earth or grounding losses. Its fun to look at, has great sound effects, and makes. What is the best way to ground a fiberglass antenna. With end fed antennas, the coax is meant to radiate as part of the antenna system serving as the ground or counterpoise and therefore you need to use a feed line choke box fc above to suppress the common mode current on the outside of the coax feed line so it does not enter the radio and cause garbled communication. A common design for a counterpoise is a series of radial wires suspended a few feet above the ground, extending from the base of the antenna in all directions in a star pattern, connected at the centre. Grounding the antenna wont improve its performance. Proper antenna grounding technical discussion mygmrs. W5bwc electronics 9108 fm 1972 gilmer, tx 75645 8111. Antenna system bonding and grounding requirements in the. The efficacy of the ground can be improved by using wide copper straps. Some ground systems can serve two or more functions quite effectively. Facility and equipment grounding to enhance equipment. Cb radio grounding the antenna electronics fmca rv.
I have an extra maxrad 58 wave antenna and this morning attached it to my guttering on the top of my house with a simple cclamp as a test. Over the air hd tv antenna grounding for lightneing and. Other antenna system grounding requirements may however pose special criteria not. Minimizing this loss is the purpose of the ground system associated with a vertical. Better to be safe than sorry, grounding the antenna and mast is. The radial our counterpoise system is connected to the smartuner rf ground. Tv antenna preamplifier, mount, rotor, cabling, grounding and much more including tv antenna installation diagram. Amateur radio station grounding and lightning protection.
This is for television antennas not ham radio, do not follow instructions for radio grounding. Carr one of the universal bits of advice given to amateur radio operators and shortwave listeners is to provide a good ground for their transmitters, receivers and antennas. Itd not pretty, but the building inspector didnt say anything when he came out to inspect the solar system running right next to the antenna ground wire. Installation of mosley classic 33 with warc and grounding system. Antenna and ground system 4 lightning arrestor a lightning arrestor is an important part of the antenna system that is located outside the building and usually close to where the antenna and ground wires penetrate. Maximumgain radial ground national contest journal. To help disperse or divert energy from lightning strikes to provide safety in case some problem or fault energizes the cabinet or equipment chassis with dangerous voltages to provide a controlled rf return path for endfed single wire feed antennas, or poorly configured or improperly. Lightning protection is a safe investment for any station.
Principles of electrical grounding john pfeiffer, p. Therefore, without radials, ground mounted vertical antennas are not much more than. According to the insurance informa tion institute, claims for lightning losses cost nearly a billion dollars in lightning protection for the amateur radio operators home lightning protection is a safe investment for any station. Among amateurs theres been a long running discussion regarding the effectiveness of avertical with an elevated ground system compared to oneusing a large number of radials either buried or lying on the ground. Ok, being new to base station and repeater building i have a very important question. No, grounding the antenna at the box is not going to help grounding for the antenna shield is provided when you use the connector on the end of the antenna coax to attach it. A coaxial cable b grounding block c electric service equipment d ground clamps e power service grounding electrode system f grounding conductors g ground clamp c d a b e f g grounding the mast. By rudy severns, n6lf verticals, ground systems and some. I would like to install a small outdoor television antenna side of the house, not the roof, and id like to be sure its sufficiently grounded. May 28, 20 proper antenna grounding posted in technical discussion. The resource is currently listed in in a single category. All vertical monopoles need some form of counterpoise in which antenna image currents flow to work efficiently.
Better to be safe than sorry, grounding the antenna and mast is the most important step when. A shortened electrical grounding system for use with a vertical antenna, particularly am limited range information stations. Telecommunications engineering and construction manual. How to ground a television or communications antenna. Antenna system bonding and grounding requirements in the usa. Base fed vertical antennas must have a good rf ground system for efficiency. Proper grounding of the antenna mast and leadin cables is. Grounding vhf base station antenna amateur radio stack exchange. First and foremost is for the safety of your family, home, and ham equipment. Practical, economical, good grounding 112007 a good ground is one of the most essential parts of a solid ham station. The counterpoise functions as one plate of a large capacitor, with the conductive layers in the earth as the other plate. Desigr ers thought that protection was not necessary in many cases because the antenna mast was relatively short 10 meters or less. This link is listed in our web site directory since sunday nov 24 20, and till today antenna grounding system has been followed for a total of 686 times.
A closer look at vertical antennas with elevated ground. A good ground system is an essential part of a good ham station for various reasons. For some antennas, the antenna is simply not complete without a radial system, or at least a counterpoise. Grounding is a very easy procedure and you require the following 3 items to effectively ground your antenna 1. Blows a breaker if a power system short connections should be big copper and short. This is a discussion of the basic principles behind grounding systems and how grounding is related to safety and the effective operation of circuit protection devices such as fuses and circuit breakers. April 16, 1981 osha rulings are in agreement with the national electrical code. I can tell you honestly that this was not so fervently discussed on the radio in earlier decades. Please consult the nec, a local licensed electrician, or a local electrical inspector for details. First off, test resistance between the metallic base of the antenna and the barrel of the.
It is alsofound that a ground system consisting of 120buried radial wires, each onehalf wavelong, is desirable. Rf grounding antenna grounding isolated grounding u. Good quality copper wire 10 awggauge is the best for an antenna for a satellite you can use 6 gauge but for an antenna we recommend 10 gauge copper wire belden. O ver the past 100 years, beginningwith marconi and continuing to this day, vertical antennas and their associated ground systems have received considerable. Can i use a ground rod to ground my antenna system. Knowing how to ground an antenna properly can make significant improvements to its performance, whereas a poor ground or earth connection can mean that its performance is.
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