Steps i would take to check and improve your system. This is not an indepth publication but simply a general guide on installing and using steppir verticals. W5bwc electronics 9108 fm 1972 gilmer, tx 75645 8111. 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. For some antennas, the antenna is simply not complete without a radial system, or at least a counterpoise. Useful radiation from an underground antenna 12 harold a. Rf grounding antenna grounding isolated grounding u.
Capacitive grounding may only reradiate these interfering signals somewhere else aboard the boat. Over the air hd tv antenna grounding for lightneing and. Simple antennas and good grounds university of hawaii. 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. 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. They rely on return ground currents and use the ground as part of the antenna system. Lightening not only kills radios but can start house fires. Site considerations for equipment installation, grounding.
Its fun to look at, has great sound effects, and makes. Grounding the antenna wont improve its performance. Some ground systems can serve two or more functions quite effectively. 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. Telecommunications engineering and construction manual. Antenna system bonding and grounding requirements in the usa. Article 810 refers to article 250, grounding and bonding, so i also will discuss its associated requirements. Cb radio grounding the antenna electronics fmca rv. Lightning protection is a safe investment for any station. About antenna grounding system the resource is currently listed in in a single category. A complete grounding system for the antenna, towers. If you find that you have resistance, youll need to determine where along the line the circuit is open. Amateur radio station grounding and lightning protection. A good ground connection is every bit as important as a good antenna in doityourself radio electronics.
One wire of the feedline connects to the base of the antenna, and the other connects to ground. The main category is grounding systems and techniques that is about grounding systems and techniques. After antennas, station grounding is probably the most discussed subject in amateur radio and it is also the one replete with the most misconceptions. View grounding accessories more about tv antenna grounding. 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. Digital ota tv now offers more channels all with outstanding picture and sound quality. May 28, 20 proper antenna grounding posted in technical discussion. Tv antenna installation guidelines for better tv reception. By rudy severns, n6lf verticals, ground systems and some. It is alsofound that a ground system consisting of 120buried radial wires, each onehalf wavelong, is desirable. History of lightning protection system design in tactical sstems many older communication systems do not have lightning protection incorporated into their design. 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. Antenna system bonding and grounding requirements in the. There is quite a bit of talk these days between amateur ham radio operators about the desirability for good grounding systems for their home radio stations. The grounding requirements for antenna cables are con tained in 810. First and foremost, grounding is for the safety of your family, home, and ham equipment.
Once youve done that, there wont be any need to ground the antenna for performance. If the antenna is unbalanced, a radial system or counterpoise is necessary for operation. The resource is currently listed in in a single category. This assumes that there are no earth or grounding losses. I would remove and replace the antenna coax connectors from both the transmitter box the. 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. A closer look at vertical antennas with elevated ground. As this antenna can only radiate above the ground plane, a monopole antenna will have a gain of 3 db over an equivalent dipole. The counterpoise functions as one plate of a large capacitor, with the conductive layers in the earth as the other plate. First off, test resistance between the metallic base of the antenna and the barrel of the. Therefore, without radials, ground mounted vertical antennas are not much more than. 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.
Review the lightning protection system record drawings on each facility at least. 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. Grounding vhf base station antenna amateur radio stack exchange. How to install an earth grounding and bond for communication antenna. Can i use a ground rod to ground my antenna system. Antenna system bonding and grounding requirements in. Proper grounding of the antenna mast and leadin cables is. O ver the past 100 years, beginningwith marconi and continuing to this day, vertical antennas and their associated ground systems have received considerable. Electronic multipoint ground system requirements 230.
This pipe then would have to be underground at least 3 feet to be effective. A closer look at vertical antennas with elevated ground systems rudy severns n6lf. I have heard people talk grounding an antenna but dont think i hav. 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. Facility and equipment grounding to enhance equipment. 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. Please consult the nec, a local licensed electrician, or a local electrical inspector for details. With the exception of the vertical dipole, a dipole on its end, vertical antennas are only half there. The national electrical code includes the requirements for grounding your antenna or mast in article 810. 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. 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. Antenna system grounding by larry d barr, k5wlf intro.
Improvements and changes to this manual necessitated by typographical errors, inaccuracies of. Cm7777hd, cm7777, cm7778 what is a distribution amplifier and do i need one. I can tell you honestly that this was not so fervently discussed on the radio in earlier decades. A shortened electrical grounding system for use with a vertical antenna, particularly am limited range information stations. Does not help with rfi does not make an antenna work better. 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. Better to be safe than sorry, grounding the antenna and mast is the most important step when. This is really from an antenna flaw, and not from the reflection of signals. 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. Experimental data are given which show that an eighthwave antenna is practically as efficient as a quarterwave antenna. 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.
Vertical antennas can have radials mounted on or below the surface of the actual ground. All communications systems need antenna towers, which naturally invite lightning strikes that can cause damage to a centers sensitive equipment. A number of antenna designs, especially those that are unbalanced with respect to ground. Proper antenna grounding technical discussion mygmrs. Minimizing this loss is the purpose of the ground system associated with a vertical. 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. 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. Grounding is a very easy procedure and you require the following 3 items to effectively ground your antenna 1. 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. Grounding systems and techniques category is a curation of 38 web resources on, notes on ground systems, grounding and reducing noise, verticals.
As a result, if the ground sucks, the antenna will also. Proper antenna grounding posted in technical discussion. 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. Nov 04, 2017 this is for television antennas not ham radio, do not follow instructions for radio grounding. The us army signal corps recently reported on the results of improved grounding techniques for mobile field tactical radio stations. On installations where the electrical utility system is owned by a private entity, consult with the private system owner. 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. In fact, short capacitiveground systems may actually invert the antenna ground signals, radiating more signals below deck than through the antenna above deck. Knowing how to ground or earth an antenna system can be a key factor in the operation of some antennas. 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.
Grounding systems and techniques category is a curation of 38 web resources on, safe,effective grounding, notes on ground systems, grounding and reducing noise. Assuming you placed your antenna outdoors, you may be lucky enough to find an outdoor water faucet near the end of. Metal frame of the building or structure where the following methods are used to make an earth connection. Maximumgain radial ground national contest journal. Blows a breaker if a power system short connections should be big copper and short. Since a halfwave dipole has a radiation resistance of 73 ohms, a quarterwave monopole will have a radiation resistance of about 36. A good ground system is an essential part of a good ham station for various reasons.
A lightning arrestor consists of a spark gap that will arc when more than a few hundred volts exists across the points. Ground impedance, and earth surface potentials of a ground system to address issues related to large grounding systems or systems in congested areas. Grounding vhf base station antenna amateur radio stack. 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. All vertical monopoles need some form of counterpoise in which antenna image currents flow to work efficiently. 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. April 16, 1981 osha rulings are in agreement with the national electrical code. How to ground a television or communications antenna. 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. Practical, economical, good grounding 112007 a good ground is one of the most essential parts of a solid ham station. I will be installing a gable antenna mount which has a 6 extender pole on my single story home. The antenna was designed to work without a ground system and although the antenna is. 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.
The ground system consists of a cable connected to a copper rod driven several feet into the earth. Guide for grounding an antenna system guide for grounding an antenna system electrical question. The best way to create a good ground connection is to use a metal cold water pipe. First and foremost is for the safety of your family, home, and ham equipment. Installation of mosley classic 33 with warc and grounding system. What is the best way to ground a fiberglass antenna. The efficacy of the ground can be improved by using wide copper straps. Desigr ers thought that protection was not necessary in many cases because the antenna mast was relatively short 10 meters or less.
Communication site building design and installation 31 3. Please consult the nec, a local licensed electrician. I inspected the wiring of my antenna with the intention of doing a write up on how it was grounded. Tv antenna preamplifier, mount, rotor, cabling, grounding and much more including tv antenna installation diagram. 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. The important thing is to eliminate commonmode currents in your antenna system, perhaps with a balun. Principles of electrical grounding john pfeiffer, p.
This is required only for certain types of antennas ones which require current flow to ground to complete the antenna circuit. The radial our counterpoise system is connected to the smartuner rf ground. Better to be safe than sorry, grounding the antenna and mast is. Proper grounding of the antenna mast and leadin cables is somewhat effective in protecting receiving equipment from. 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. 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. The first thing to know is that there are three functions served by grounding in ham shacks. 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. Gps antenna installation guidelines general information installations must be made by qualified personnel, and in accordance with federal regulations. How much signal do i lose going through a splitter. This surprised me until i had an email conversation with joe reisert, w1jr, the original designer. Wheeler february 26, 1960 an underground antenna delivers power to the surrounding conductive medium, and a fraction of the power goes out as radiation above the surface. Other antenna system grounding requirements may however pose special criteria not.
Ieee industry applications society atlanta chapter january 19, 2010 meeting 2. I will discuss the nec bonding and grounding requirements that apply to radio telescope. Power, grounding, bonding, and audio for ham radio safety, hum, buzz, and rfi jim brown k9yc. This is for television antennas not ham radio, do not follow instructions for radio grounding. Power, grounding, bonding, and audio for ham radio safety, hum, buzz, and rfi. Ok, being new to base station and repeater building i have a very important question. Base fed vertical antennas must have a good rf ground system for efficiency. 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. 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. A copy of the faa advisory circular can be obtained at. This counterpoise usually consists of a system of radial wires placed either on the ground or elevated above ground. Tests of groundscreens show them to be ofnoimportance whenadequate ground.1492 50 876 1070 1150 1510 1092 1011 668 1392 168 73 994 854 1157 119 1267 454 640 342 458 1601 1260 143 554 76 1641 475 128 1579 1199 1084 377 675 367 722 974 1405 602 148 592 1233