Ham radio coverage calculator Two terrain databases are available here: the FCC's legacy 30-second terrain database, and the GLOBE 1 km Base Elevation database from the National Geophysical Data Center. This calculator assumes nothing is in the way of the radio signal between the antenna and the Dec 28, 2024 · SignalServer is a simulation that can provide insight into geographical coverage of a transmitting system. Use the μV to dBm calculator to calculate the equivalent -107 dBm amplitude. The most powerful radio service available. It's ideal for the ham radio operator, shortwave listener, or other radio enthusiast. 1 day ago · Calculate and Design Antennas Antenna Calculators are online tools used by amateur radio operators to design and calculate dimensions for various types of antennas. 100 147. 65 GHz, and 5 GHz coverage areas quickly. Here are the instructions how to enable JavaScript in your web browser . 6 days ago · Amateur Radio Roundtable to Broadcast Live from Hamvention May 16, 2025. Current Ham Radio Propagation. The main purpose for the existence of IP Sound is to provide low quality audio 8-16kHz, with low latency for use together with remote control software for "ham" radio amateur equipment. This type of antenna is easy to construct and can be used for various frequencies, making it a favorite among amateur radio enthusiasts. RadCom online Propagation Prediction Tools. RadCom Basics; Alex Discovers Amateur Radio; Search Dec 3, 2021 · Alex Discovers Amateur Radio; Search; New web-based RSGB EMF calculator. EXAMPLE of RF Propagation Calculator: INPUTS: Frequency (Fr): 850 MHz; Receiver Sensitivity: -106 dBm; Transmitter Power (Pt): 5 Watts; Transmitter Antenna Height (Ht): 4. Astronomy: Telescopes, astrophotography equipment, and optical accessories. Dec 1, 2022 · 1. Washington Monument Lat/Long: (38. Current Ham Radio HF Propagation. 8 : Charlotte, One Wells Fargo Center: Mecklenburg: W4BFB: OPEN Live tracking and mapping of APRS data worldwide. Antenna Height of 1st Station (ASL) Antenna Height of 2nd Station (ASL) Feet Metres For the 1st station, the Radio Horizon is away. Examples of such devices are mobile phones, routers, computers, two-way radios, credit cards, satellite receivers, televisions, and other equipment that transmits rotctl, part of the free cross-platform open-source package libhamlib-utils (hamlib) will not only calculate the distance and bearing, it will instruct a rotator to point there, though you don't have to have a real rotator to run it. 889484, -77. com. This is due to the refractive effect of the Earth's atmosphere, which causes RF signals to propagate in a slightly curved line over long distances, pushing out the effective horizon distance. For starters, thank you very much for your detailed reply and the insights you provided. 4 GHz, 3. callsign, amateur radio, ham radio, pictures, DX. The Effective Isotropic Radiated Power (EIRP) is the apparent power transmitted towards the receiver, if it is assumed that the signal is radiated equally in all directions, such as as a spherical wave emanating from a point source; in other words, the arithmetic product of the power supplied to an antenna and its gain. By offering a visual snapshot of the current ionospheric conditions, these maps empower users to make informed decisions about optimal frequency selection and propagation paths. DXProp DXprop is a radiowave propagation forecast freeware for ham radio operators, permits to predict propagation on 12 frequencies. It is a very nice Great Circle Map Generator, centered on your specific location. The National Association for Amateur Radio ® 225 Main Street Newington, CT, 06111-1400 USA Tel: 1-860-594-0200 | Fax: 1-860-594-0259 Toll-free: 1-888-277-5289 hq@arrl. The J-Pole antenna is a type of omnidirectional antenna widely used in amateur radio, especially for VHF and UHF bands. Jan 21, 2016 · Values for antenna height above average terrain (commonly abbreviated "HAAT") can be calculated using this form. Common FAQs. Note that buildings and other obstructions is not taken into consideration when calculating line-of-sight using this tool. 64 444. 30 votes, 37 comments. North America Frequency Bands 915 MHz (ISM Band) Mar 20, 2019 · It is designed for ham use and GMRS, but say you want to know the coverage of a UHF repeater, say, at 451 MHz while it won't let you select 451 MHz exactly, it will let you input 462. The 75 µs deemphasis network rolls off the audio. Find Your Opening on the Map. The map is created using lat/long info, and hops from node to node that data travels. If you are wondering what Amateur Radio is about, it's basically a two way radio service where licensed operators throughout the world experiment and communicate with each other on frequencies reserved for license holders. For more information on various map types and the significance of a rectangular Mercator Map in relation to HF amateur radio coverage of a directional HF radio Oct 31, 2020 · An RF Engineer in Quebec (whom is also an amateur radio operator) has a website with a free online calculator that will help the knowledgeable radio user visualize an estimate of what there coverage would be based on many of the fundamental factors that affect radio coverage. I always have hard time calculating the offsets for repeaters so I made this tool: Aug 5, 2021 · The National Association for Amateur Radio ® 225 Main Street Newington, CT, 06111-1400 USA Tel: 1-860-594-0200 | Fax: 1-860-594-0259 Toll-free: 1-888-277-5289 hq@arrl. Last update of this index page: Monday, October 2, 2023. Bray, K2LMG, in 1961 and re-published by Ed Tilton, W1HDQ, in all three editions of "The Radio Amateur's V. Hi folks! New ham here. For full functionality of this site it is necessary to enable JavaScript. net provides recognition and enjoyment to the people who use, contribute, and build the site. This map shows real-time radio propagation from stations operated near 144 MHz. 020 927. These tools are part of the new Nautel RF Toolkit, available free online at the website www. Just a quick update about new tool I created recently. 2 meters; Distance: 15 Km; OUTPUTS: Max. Radio Mobile Online is a radio wave propagation prediction tool dedicated to amateur radio. The results presented by this calculator are based on input values and basic theoretical principles of wireless. Leland J. RF coverage maps can be used for a variety of amateur radio purposes, including: Repeater Planning: Assess potential sites to ensure maximum coverage for your community. You should use this calculator as a tool to understand what can be achievable based on abovementioned assumptions and limitations. Current HF Band Conditions Online Map. It uses data gathered by APRS-IS. true. Enter your desired frequency (MHz) of operation (i. Mar 23, 2017 · In land mobile radio, the F(50,50) value is employed in calculating the "service contour. Antenna Height of 1st Station (ASL) For the 1st station, the Radio Horizon is away. The following equation or formula is used for the antenna range calculator. It is a graphical representation of MUF within a 3000-kilometer range, allowing amateur radio station operators to estimate the best frequencies and paths for effective communication. 54 dB; Formula/Equation used in RF May 5, 2018 · Repeaters Frequency Calculator. For the 2nd station, the Radio Horizon is away. Like its predecessor, the FT-991A is creatively designed to fit into a very compact (W9. Frequency Offset Tone Up / Down Location County Call Use Modes; 145. This tool is invaluable for amateur radio operators, emergency responders, and professionals relying on HF bands for communication. 8 dBc spaced 363. DMR in Australia; Three Digital Radios – The Good, The Bad and the Ugly. Real time radio propagation map. Aug 15, 2012 · You can only get a general idea of coverage range if you know the antenna height at both ends. What is amateur radio? FAQ; First steps; Your station. org ARRL Donate Now WebSDR is a software-defined radio receiver accessible online, enabling multiple users to tune and listen independently to various signals worldwide. " The F(50,10), which means that the predicted electromagnetic field strength occurs at 50% of the receivers 10% of the time, value is used in the calculation of the "interference contour. I will present below a set of attenuation curves representing typical behavior on all ten bands including 160-80-60-40-30-20-17-15-12-10m. This is the minimum level required at the receiver. F. Lassen 292 km (182 miles) away, using my 5W Kenwood TH-F6A HT. What is an Efhw Antenna? An EFHW (End-Fed Half-Wave) Antenna is a type of radio antenna commonly used in amateur radio. May 2 Welcome to Reddit's own amateur (ham) radio club. T attenuator calculator – Calculate the resistor values for a T May 8, 2025 · The DXZone is the largest human created library of amateur radio Web sites, it currently lists more than 20,000 links organized into more than 600 categories. I teach the uk amateur radio exam courses and this will be a great asset. May 8, 2025 · Explore a comprehensive directory of loop antennas for amateur radio operators. 5625 (GMRS freq) which will not give a noticeable difference. Welcome to Reddit's own amateur (ham) radio club. A special two day live webcast will take place at Hamvention in Xenia, Ohio on Friday and Saturday. Here is a simple line of sight calculator that will do the complicated math for you to determine just how far the horizon is from your HT or your base station antenna at any height above level and flat ground (or calm water) on the VHF/UHF ham bands. 6 dBd Gain and Boom Length to 39 λ. – Mark Twain Dec 29, 2015 · A recent 'year end review' posting in the Amateur Radio Weekly blog, reminded me of great little piece of online software that might interest a lot of hams. Propagation along the grey line is very efficient. 14000 to 14350 kHz ham radio: 19 meters: 15100 to 15600 kHz broadcasting: 17 meters: 18068 to 18168 kHz ham radio: 16 meters: 17550 to 17900 kHz broadcasting: 15 meters: 21000 to 21450 kHz ham radio: 13 meters: 21450 to 21850 kHz broadcasting: 12 meters: 24890 to 24990 ham radio: 11 meters: 25670 to 27990 kHz broadcasting, CB: 10 meters: 28000 Radio-frequency engineering (RF engineering) is a field of engineering that deals with devices that transmit or receive radio waves in the radio frequency spectrum (3 kHz to 300 GHz). 10 GHz Amateur Radio; Amateur Radio Microwave – It’s easier than you think The two rays method and landcover path loss estimation are based on my 40 years experience in radio propagation. These maps allow you to see the compass bearing from your QTH to other DXCC entities. Jan 15, 2024 · Bearing calculator for directional antenna NMO antenna to HT radio connector recommendation May 2, 2025; Amateur Radio Antennas; Replies 5 Views 302. The VHF Propagation Path Profiler presented here is a comprehensive application that allows us to graphically render and mathematically compute various relevant VHF/UHF propagation metrics including VHF propagation path losses, over the realistic terrain profile between any two point-to-point locations on the surface of the earth. It was designed for amateur radio operators. RUSS G0OKD Oct 3, 2024 · The J-Pole Antenna Calculator is a tool designed to help ham radio enthusiasts and other radio operators to determine the optimal dimensions of a J-Pole antenna based on a specific operating frequency. Jan 14, 2010 · There is also atmospheric conditions. Draw concentric circles on a copy of the map at 2, 4, 6, 8 and 10 miles from the antenna. Kites For Lifting Antennas From The Hawaii Ham Radio Information Pages Kites For Antenna Lifting - From G6LFT / M0CUQ Ladder-Line Back Pack Special-- From W2IK Liquid Antennas -- Not April 1 stuff Log Periodic Antenna Calculator Full Wave Loop Antenna 10M thru 80M -- From Western Canada's Ham Radio YL Site Loops-- From The ARRL EIRP (Effective Isotropic Radiated Power) is the measured radiated power of an antenna in a specific direction. • My Ham Station • HF Contesting • Irish Contesting • Buy And Sell It • Ham Links • Overlay Maps • Ham Maps • APRS Maps • Flags • Ham Downloads • Guestmap Archives • My Ham Station: Here you will learn about EI8IC, a brief biography of my radio amateur 'career', and be able to see the radio equipment and aerials that I use. It will calculate either short path or long path. Links:Radio Mobile Online: https://www. Predicting Signal Strength: HF propagation calculators estimate the signal strength and reliability of communication between two HF radio stations based on various input parameters, including the frequency of transmission, transmitter power, receiver sensitivity, and distance between the stations. One major reason for this is that the D layer, which absorbs HF signals, disappears rapidly on the sunset side of the grey line, and it has not yet built upon the sunrise side. It is designed for the Ham radio hobbyist, but may be useful to others as well. Antennae characteristics are so fundamental to this question at this frequency that an answer cannot be sensibly given without some sort of antenna spec. These radio frequency calculators help with unit conversion, attenuator design, antenna design, radars, and various other basic calculators. Note that 5 to 7 metres is excellent but that diffraction with ground issues will be your distane limit constraint at very great distances. Introduction. Enter the desired frequency then click on Calculate and the optimum values for that combination will be displayed in feet, inches and fractions of inches, and in meters. org ARRL Donate Now 2 days ago · The DXZone is the largest human created library of amateur radio Web sites, it currently lists more than 20,000 links organized into more than 600 categories. VOACAP Online is a web-based tool for calculating propagation conditions for amateur radio contacts on any band and mode. Free azimuth maps may be generated using these on-line services: Azimuthal Map page - NS6T AJ_PROJ . The evaluation is made for a 3,000 km radio path for unification. PI attenuator calculator – Calculate the resistor values for a PI attenuator. Amateur radio: A 21st Century hobby; Amateur Radio: A World of Possibilities; GB1SS: schools speaking to Tim Peake; More RSGB videos; Read. Current Ham radio conditions. Setting up; Operating; Antennas; EMC considerations; Watch. " There is one frequency slot defined with the standard radio preset LongFast. The total line of sight distance is Miles Km. For 800 MHz, you can input 903 MHz which will be pretty close to 800 MHz coverage. Then you can use the radio horizon formula to figure the approximate line of site distance. 25 Meter Amateur Radio Repeaters Location Output (MHz) Input(MHz) Input PL/DPL Output PL/DPL Callsign Affiliated Group Comments Denver - Guy Hill: 224. It uses data gathered by Automatic Packet Reporting System-Internet Service (APRS-IS) from packet stations in the amateur radio service. It doesn’t need to be difficult, but you have to start with the right understanding. Radio transmissions at these frequencies are usually limited to "line of sight" between station antennas. Practical Applications of RF Coverage Maps. everything RF has created a series of RF calculators to help engineers and students with common calculations that they need to conduct frequently. Apr 20, 2017 · Radio Line of Sight Calculator for use on VHF/UHF Ham Bands This will give you an approximate "line of sight" distance. org ARRL Donate Now Jun 5, 2021 · The Antenna Calculator for Half-Wave Dipoles. You can do this by providing your name or callsign and email address. NGØE's VHF Propagation Map displays current VHF band openings during the past hour. , to antennas, the points could be defined as Long / Lat coordinates + an elevation, for instance) and see if there is a line-of-sight path between those two points given (1) the curvature of the earth (2) changes in terrain. This calculator calculates the theoretical LOS and actual radio horizon (service range) of an antenna. Line-of-sight propagation - Wikipedia, the free encyclopedia The most common material for home building small ham radio loop antennas is common copper plumbing pipe. 533-14. HF Radio Propagation Search Terms. The image above illustrates the steps required to determine the antenna coverage range, taking into account the following inputs: Antenna Transmit Power (Pt) Transmit Antenna Gain (Gt) Cable Loss 3 days ago · Now includes a 3 Year Manufacturer Warranty! The FT-991A is the next-generation of the widely popular FT-991. They help hams build efficient antennas like log periodics, verticals, Yagis, and loops by providing dimensions and spacings. Resonant Frequency Calculator – Calculate the resonant frequency of a parallel inductor and capacitor tuned circuit. Feb 28, 2025 · There is more incorrect information and wrong thinking about impedance and SWR than just about any other topic in ham radio. Nov 5, 2023 · To anyone looking to acquire commercial radio programming software: Please do not make requests for copies of radio programming software which is sold (or was sold) by the manufacturer for any monetary value. Communications Manager | December 3, 2021 Apr 8, 2024 · Got Crypto? You can help keep the site running with your crypto donations! BTC: 1BJJ2u6iPLMfjCsNa3RsjCBwB3kPTsmbXw. 2” x D9. 900 51. However, these can’t account for stations with high-gain antennas or for radio amateurs using more sensitive modes, such as FT8. 700 442. SPLAT! is an RF Signal Propagation, Loss, And Terrain analysis tool for the electromagnetic spectrum between 20 MHz and 20 GHz. 0” xH3. After factory reset the radio will be set to frequency slot 1 with a center frequency of 869. Specifying a Gain > 21. 035278) LOC: FM18lv53SL The 10-character grid square contains five pairs of coordinates: FM, 18, lv, 53, and SL. Current Ham Radio Propagation Conditions. GigaParts is the premier destination for the latest in technology products and hobby gear, catering to a wide range of interests: Amateur Radio: A variety of amateur radio equipment and accessories. 03. See where your radio signal gets out and plot paths between radio stations with this free tool by Roger Coudé VE2DBE. Oct 9, 2020 · Recently, I worked a station through the W6CX Mt. Go to the Radio Mobile Online website and create a free account. 750 446. Applications of SPLAT! include site engineering, wireless network design, amateur radio communications, frequency coordination, communication system design, and terrestrial analog and digital television and radio broadcasting. Manual. org ARRL Donate Now May 12, 2025 · World's leading amateur radio web site with news, technical articles, discussions, practice exams and more. DOGE: DKkezoWGaoQKaopxk8jgTBGUVZ39g2TBrE The Ham Intelligent Calculator, also called Hamic, is a program designed to simplify a number of calculations commonly used by Hams. So, I went ahead and The two rays method and landcover path loss estimation are based on my 40 years experience in radio propagation. Create 900 MHz, 2. W. As a matter of fact there is a forum here on that topic where people post distant police/etc calls they've received. 8 and 54 MHz in the amateur radio service. 3”) rugged case and will deliver up to 100 Watts solid output power (50 Watts on 140/430 MHz) on SSB, CW, AM, FM, Packet and C4FM Digital on the popular HF/50/140/430 MHz bands. It uses digital terrain information and a mathematical model to simulate radio transmissions between two fixed sites (radio link) or between a fixed site and a mobile (Radio coverage). It isn’t what you don’t know that gets you in trouble, but what you know for sure that just ain’t so. With the program available here, the expected range of VHF radiotelephony systems can be calculated using the ground wave propagation. Historical Background. g. " WebSDR is a software-defined radio receiver accessible online, enabling multiple users to tune and listen independently to various signals worldwide. 000: 222. If you have no particular preference within a given ham radio band, then simply enter its center frequency (i. Find resources, plans, and projects for building and using loop antennas in your ham radio setup. I don't think I'm doing everything just quite right though. Note that we have not used the Minimum Detectable Signal of -130 dBm in this calculation, as our interpretation from the specification is that it represents the The radio horizon / service range of an antenna will always be slightly further than the straight line-of-sight distance to the horizon. Welcome to StationMapper. H. net Gold Membership Buckmaster OCF Dipole Antennas Antenna Support Rope Line-Grips Harken Stainless Steel Pulleys RF Chokes CQ Magazine Archives World Prefix, WAS, and Great Circle Maps Custom Great Circle Maps HamCall Mousepads Custom Name Badges Amateur Radio Operator Certificates Antenna Wire Screw-on Cable Use the following entry areas to define your antenna requirements. AZMap - Azimuthal maps generator AZMap is a freeware Windows program for the Windows PC which will generate, display, and print an Azimuthal-Equidistance (A-E) map of the world, centered at any point on the surface of the earth (except very near the poles). org ARRL Donate Now The home of the online HF propagation prediction tool, 'proppy', providing on-demand point-to-point and area predictions using the ITU's ITURHFProp application in accordance with ITU-R P. Since 1998, a group of radio amateurs has been reviewing new sites for listing every day and evaluating the best place to list them. " Sep 24, 2018 · The theoretical radio horizon for a 50ft antenna on the flat is only about 4. This calculator is designed to give the critical information of a particular beam antenna, in this case a three element Yagi, for the frequency chosen. All requests will be deleted and a forum infraction issued. HamCall DVD/USB/Download HamCall. One popular option that offers simplicity and versatility is the random wire antenna. Membership comprised of the various FCC certified Surface wave (Ground wave) Propagation on amateur Radio HF Bands Let us now take a look at some of the aspects of surface Wave propagation as it manifests itself on amateur radio HF bands. It is worth noting that 868 MHz is generally the most popular frequency band for Meshtastic in Europe. For hams unable to attend Hamvention in person, Amateur Radio Roundtable will provide multiple video feeds and reporters covering the event. 8 / 118. The live stream will be active very informative and useful site all the information you need on one webpage the calculator is brilliant . For a Radio Coverage study, a colored plot over a topographical map is produced. 7. It is also called Equivalent Isotropic Radiated Power. nautel. Aug 14, 2024 · To calculate the length of an EFHW antenna, divide 468 by the frequency in MHz. Nautel has partnered with RF engineer Roger Coudé, the author of “Radio Mobile”[1] to provide simple, fast online VHF/UHF coverage mapping and point to point analysis worldwide. 6miles but that to someone on the ground - if the other guy has a 50ft mast too, then the distance is about 16miles. 805 224. Oct 1, 2017 · Hello all, I've been playing around with Radio Mobile for years to generate coverage maps. It's designed to figure the distance from your radio to the line of sight horizon, but if you put in the height of the repeater antenna and assume yourself as the horizon, you'll get about the same effect. eHam. Real-time watching of worldwide ham Included is a complete set of GoogleMap-based, HTML-driven maps which show the most current pattern plots of all licensed US and Canadian mediumwave broadcast stations from 530 – 1700 KHz. radio distance between Tx-Rx: 16. I know radio coverage can never be 100% guaranteed per-se, however, I've been tinkering around with the software tonight. Here is a simple line of sight calculator that will do the complicated math for you to determine just how far the horizon is from your HT or your base station antenna at any height above level and flat ground (or calm water) on the VHF/UHF ham bands. 2 Meter Propagation. Local Coverage: Within this area, you should be able to receive the radio station on almost any radio with moderately good to very good reception. ERP & EIRP Calculator – Calculate effective radiated power from your antenna. This website was developed to help radio and TV DX enthusiasts locate a station near them. Below is the line-of-sight plot between the two summits using scadacore. C4FM and WiRES-X; D-Star; DMR Repeaters c-Bridges and Networks; DMR Reflectors; FT8 and GridTracker – Digital Amateur Radio; Microwave. 146. Computers: Custom PC builds, gaming computers, and ready-to-go PCs. The map ge Apr 18, 2025 · Larsen Electronics was founded in 1965 by Jim Larsen K7GE (I've forgotten his original W7 callsign). Oct 2, 2023 · The first version of this web site came on-line on Thursday, December 13, 2001. To build the largest and most complete Amateur Radio community site on the Internet - a "portal" that hams think of as the first place to go for information, to exchange ideas, and be part of what’s happening with ham radio on the Internet. many thanks. RF coverage maps: to expand map image right click and open in new tab. It is used in planning radio, television broadcasts, cellular networks, and emergency communication systems. When it comes to amateur radio, having a reliable and efficient antenna is crucial for achieving clear and strong signals. There is no guarantee of results. It is used by RF engineers, ham radio operators, mobile communications engineers, and others to help determine placement and effectiveness of antenna structures and repeaters. Coax Loss Calculator; Contests; Digital Radio. The Radio Coverage Tool is based on the Longley-Rice World's Largest Supplier of Amateur Radio, Ham Radio, and Communication Equipment. Diablo repeater from the summit of Mt. Create for any frequency other than 88-107MHz "FM Band This map shows real-time radio propagation from stations operating on 11 bands between 1. It shows the how stations are positioned to each other over larger distances. For a Radio Link study, the output of the mathematical model predicts success if the fade margin of the received signal is greater than zero. 400 1 day ago · The "grey line" is a band around the Earth that separates daylight from darkness. May 8, 2025 · The DXZone is the largest human created library of amateur radio Web sites, it currently lists more than 20,000 links organized into more than 600 categories. Antenna Coverage Distance = 3147 meters; Antenna Range Calculator Equation. Mar 15, 2016 · The National Association for Amateur Radio ® 225 Main Street Newington, CT, 06111-1400 USA Tel: 1-860-594-0200 | Fax: 1-860-594-0259 Toll-free: 1-888-277-5289 hq@arrl. EIRP (Effective Isotropic Radiated Power) is the measured radiated power of an antenna in a specific direction. They can not reflect all aspects of real installation. The extra information offered by readers like you goes a long way in advancing the hobby and is a big part of what makes amateur radio so great. 373 Hz apart. The display shows worldwide activity from the last 15 minutes and is automatically updated about every minute. 15 for the 40 meter band). Power is over-rated. Sales, Supplies, and Service. Every month RadCom magazine carries HF propagation predictions to more than 30 locations. How does the height of the radio tower affect the radio The VHF Propagation Path Profiler presented here is a comprehensive application that allows us to graphically render and mathematically compute various relevant VHF/UHF propagation metrics including VHF propagation path losses, over the realistic terrain profile between any two point-to-point locations on the surface of the earth. May 8, 2025 · This grid system is used worldwide by amateur radio operators for many aspects of ham radio. In this video, we dive into the fascinating process of creating Radio Repeater Range Maps and demonstrate how to plot and calculate the range of your local A DX Toolbox searches the web for you, gathering information on solar and geomagnetic conditions that affect radio propagation. 39 Km; Path Loss: 114. org ARRL Donate Now This map shows real-time radio propagation from stations operated near 144 MHz. Calculation of radio ranges in the VHF range. He passed at age 81 in February of 2000 after 68 years in ham radio and 34 years in business. JavaScript must be enabled to use see the real-time graphics. Jul 27, 2011 · \$\begingroup\$ Given enough antenna height and suitable antennae range is sensibly unlimited. 2 meters; Receiver Antenna Height (Hr): 4. Please see this link for more information. 80m/40m: better at night, regional coverage; 20m/15m/10m: long-distance DX possible, best during high solar activity; This calculator provides a **best-case propagation distance** — real-world conditions like terrain, noise, antenna height, and polarization can reduce effective range. The map shows activity from the past hour. 2/16/2008 3 National Conference of Volunteer Examiner Coordinators (NCVEC) A private not-for-profit voluntary association. The following real-time map courtesy of Andrew Rodland, KC2G is updated every 15 minutes. Nov 30, 2014 · Radio Mobile Online’s terrain data helps account for these factors, making its predictions reliable for rural and open areas. If you’re considering getting your ham radio license or you’re trying to choose a radio service that’s right for you, the answer is simple – amateur radio, also known as ham radio – has the longest range, most power, and most flexibility of any radio service that is available to the general public, once you get a license. I used these facts in a simple computer program to calculate the total deemphasized noise contributed by the subcarriers between 175 kHz, which demodulates to 15 kHz audio, and the last one at 198. This free online tool takes antenna height and the topographical formations of the earth to calculate the line-of-sight of a radio path. e. How to Tune a monoband HF Vertical Quarter Wave Ham Radio Antenna; How to build a low-band (40m, 80m and 160m) antenna; How high should my dipole be? What is the report for the IOTA contest; Quarter Wave -vs- 5/8ths Wave Vertical; Quick SWR Calculator for Vertical and Dipole Ham Radio Antennas; TOKYO HY-POWER HL-700B 600 Watt Amplifier purchase The actual distances were taken from a "path loss versus distance" graph which was first discussed by D. May 8, 2025 · IP-Sound IPSound is a Free application for audio exchange client to client over a TCP/IPv4 network (Lan or Internet). VHF/UHF Line of Sight Calculator. Hi Lew. Some amateur radio operators are able to "talk around the world" via skip or similar means with very little power. Apr 5, 2018 · Chris Warren Post author April 7, 2018 at 01:42. 3. v North Carolina amateur radio repeater database for ham repeaters in the US, Canada, and Mexico. The digital sidebands are composed of OFDM subcarriers at −45. 525 MHz. The 50watts or 3dB gain is not going to make much difference. Current solar conditions Ham radio. 55). This calculator enables you to test the design of an octagonal loop antenna and to answer "what if" questions until you arrive at a design that meets your needs without a lot of experience in electronics. I am looking (and have looked a lot) for a tool that will allow me to form a line between two points on the earth (e. 600 224. "2 Oct 3, 2024 · The calculation of radio distance is crucial for ensuring effective communication coverage, minimizing signal overlap, and optimizing the placement of radio towers. The results of this range calculator also apply approximately to the conditions in the upper SW area, for example for CB radio and amateur radio operation in the 10m Nov 29, 2017 · One easy way to determine the best orientation for your antenna is to use an azimuth map; a world map which has been set so that all the directions on that map are real antenna directions from one central point. 825 444. 6 MHz: 118. With a protractor or other method draw bearing lines from the antenna at angles of 0, 45, 90, 135, 180, 225, 270 and 315 degrees. The result will be the length of the antenna in feet. To generate an RF coverage map using Radio Mobile Online, all you need to do if follow the three easy steps below. login help/register; 04:13:58 UTC 12 May 2025 ; Welcome to Reddit's own amateur (ham) radio club. Line of sight simply means that there is a "radio horizon" from your antenna stretching out to the earth's horizon or other structures which normally blocks or attenuates the radio signals. One of the best tools to forecast HF (high-frequency) propagation is the online map (chart) shown below. "Jim" Larsen was born in 1919 and got his ham ticket in 1932. 6 dBd or a Boom Length > 39 λ will limit the design to 21. the author of “Radio Mobile”[1] to provide simple, fast online VHF/UHF coverage mapping and point to point analysis worldwide. 2900-0. Coverage Maps. It displays AM Radio Station range, FM Radio Station Range, and TV Radio Station Range, as well as Ham Repeaters in all 50 states. Enter the elevation and antenna height in the calculator. 402 Mar 23, 2017 · In land mobile radio, the F(50,50) value is employed in calculating the "service contour. xqqe rukf kawffa eyv axwxcq lpeav vqnvok qaep hgny jdor