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The document provides a detailed guide on modifying an inverted-L antenna to include the 160 meters band. This enhancement allows amateur radio operators to utilize the lower frequency effectively, which is crucial for long-distance communication, especially during the night. The inverted-L design is popular due to its compact size and ease of installation, making it suitable for various environments. By adding top band capabilities, operators can engage in DXing and contesting on 160m, expanding their operational range and opportunities. The guide includes practical tips and considerations for construction, ensuring that the antenna maintains its performance across the extended frequency range. It discusses the necessary adjustments and materials required for the modification, along with potential challenges and solutions. Whether you are a seasoned operator or a beginner, this project can enhance your station's capabilities, allowing for more versatile operations and improved signal quality on the 160m band.

The Icom IC-746 is quite a popular HF/VHF multimode transceiver which has one shortcoming in its standard configuration when used to operate modes requiring good medium-term frequency stability.

Designers and manufacturers of radio Frequency antennas. HF - 3000 MHz TET Emtron HF Yagis, Antennas for Wireless applications, Marine antennas, Land mobile, Mobile antennas.

It is a application which can be used for troubleshooting CB radio faults, by giving a graphical display of the normal operating frequencies generated by various parts of the CB radios circuits, it can help you identify if a frequency is incorrect or even missing. Another good use for this software is simulating possible frequency expansions, as it allows you to choose any frequency that the PLL is capable of generating, so you can see what the radio will allow you to get !

Frequency counters, bug finder, RF testers, distributed by WiMo Antennen

Calculate online, ERP in dB and dBi given PWR Frequency Coax lenght and type and antenna type

The document is a technical guide on designing RF filters for radio frequency applications. It covers topics such as interference suppression, band-pass filters, and low pass filters, with a focus on filter design and circuit filters.

This is an incredibly simple and cheap frequency counter with binary readout, based on the ideas of Onno PA2OHH.

This article describes the antenna for Low Frequency Beacon. It originally appeared in the "Lowdown" for Oct. 1999.

Organization of Minnesota repeater owners and users, and Minnesota frequency coordination.

This is the table of contents to a list showing how the radio frequency spectrum is allocated to different users in the United States.

Are you suffering from TVI? Then why not try this filter for size. It is a three-stage high-pass filter that blocks low-frequency 50MHz signals while letting through UHF TV.

This modification will allow the MkIIG to transmit on most of the frequencies that it receives on.

The Olivia transmission system is constructed of two layers: the lower, modulation layer is an (almost) classical Multi-Frequency Shift Keying (MFSK) and the higher layer is a Forward Error-Correcting (FEC) code based on Walsh functions.

RF and Microwave Power Amplifier and Transmitter Technologies, amplifierlinearity, efficiency and available RF power devices.

The Considerate Operator's Guide shows frequencies generally recognized for certain modes or activities (all frequencies are in MHz).

Table of Frequency Allocations as published by the Federal Register and codified in the Code of Federal Regulations remains the legal source material.

Frequency database for Germany. Emergency services, aircrafts, radio and paging system with over 2000 frequencies from all over Germany.

How to make a half l or quarter l coax cable for a specific frequency

Shortwave frequency list and swl links

Where to look on the Bands for SSTV

The NCDXF/IARU International Beacon Project operates a worldwide network of 18 high-frequency radio beacons, continuously transmitting on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz. These beacons, initially launched in 1979 with a single station and expanded to the current 18-beacon system in 1995, provide reliable signals for both amateur and commercial users to assess current **ionospheric propagation** conditions. The system's design, construction, and operation are managed by volunteers, covering hardware and shipping costs. The resource details the evolution of the beacon network, including the transition from Kenwood TS-50s transmitters to Icom IC-7200 radios with a new controller design implemented in 2015. It explains how listening for these 100-watt signals, transmitted to vertical antennas, allows operators to determine band openings and optimal propagation paths globally. The content also references three QST articles providing historical context and technical specifics of the beacon project. Practical information includes methods for identifying transmitting beacons via a schedule or specialized software like FAROS and Skimmer, which integrates with the **Reverse Beacon Network** for automated monitoring.

Amateur Radio Projects & Kits for homebrewers, includes DDS,sound card interface,programmers, hamcom, frequency counter, RF Power Meter, modems and more.

This online microstrip patch antenna calculator determines the length and width of a microstrip patch antenna for a given frequency

Modification to connect a frequency counter to a MFJ-9406 50 MHz transceiver by ON6MU

Definition of radio frequency bands, hf vhf uhf etc.

17-Element Very High Frequency/Ultra High Frequency Log Period Dipole Array

This table gives the minute and second of the start of the first transmission within the hour for each beacon on each frequency.

RadioComm can be used to program your Icom radio's memory, or to create nice radio-frequency spectra or to interface your radio to a huge database of frequencies.

The _Italian VHF Beacons_ resource provides a detailed listing of active and QRT amateur radio beacons operating across VHF, UHF, and SHF bands within Italy. Each entry specifies the beacon's callsign (e.g., IQ1SP/B), operating frequency (e.g., 144.411 MHz), QTH locator (e.g., JN44VC), effective radiated power (ERP) in watts, and antenna configuration (e.g., Big Wheel, 4x Dipole, Yagi). This data is crucial for radio amateurs involved in propagation studies, equipment testing, and long-distance (DX) communication on these higher frequency bands, offering fixed signal sources for monitoring. This compilation, last updated in October 2005, serves as a historical snapshot of Italian beacon activity. For instance, it lists several 144 MHz beacons with ERPs ranging from **0.1W** to **10W**, and higher frequency beacons such as I8EMG/B on 1296.880 MHz and I3EME/B on 24192.132 MHz. The inclusion of QRT (Quiet Radio Teletype) status for many entries indicates the dynamic nature of beacon operations over time. Users can utilize this information to identify potential signal sources for band openings or to calibrate their receiving equipment against known transmissions.

This was the blogger home page of the Resonant Frequency podcast. Follow the link to get to new web site.

A free radio station that is transmitting world wide on several shortwave frequency 's with loads of pirate and freeradio information.

Frequency coverage: 3.75 MHz to 4.00 MH transceiver for 75 MHz band

This program intended for electronic circuit analysis (mainly for Linux). ViPEC is a powerful tool for the analysis of high frequency, linear electrical networks.

An online J-Pole antenna calculator that need just to input the frequency and calculates in inch size of each element

reduce or completely eliminate interference from almost any local source whilst leaving the wanted signal relatively unaffected, even though it may be on the same frequency

This modification will expand the tx frequency range of the Yaesu FT-991 from allowing just ham radio bands, to all bands 1.8 - 30MHz and 50-54 MHz.This information is solely for use by licensed members of MARS (Military Affiliate Radio System) or CAP (Civil Air Patrol)

The Rock-Mite is a 40m CW kit offered by Small Wonder Labs . It features built-in keyer, direct conversion receiver with a crystal RF bandpass filter, 500 milliwatts of power, and switchable frequency offsets to work around QRM

Spiral antenna belong to the class of frequency independent antennas. Antennas with a very large bandwidth.

homebrew a frequency counter by M1HOG

Two Delta-Loops in phase. The purpose of this article is to propose an antenna with a high gain, a high efficiency and a very low price that is easy to build for any frequency.

This calculator is designed to give the horizontal length of a particular dipole including Tees, antenna, or one side of it, for the frequency chosen. Enter the desired frequency and select the desired calculation from the drop box

This is a SSB and CW transceiver for the 80m and 20m bands. It produces 25 Watts out and uses a digital frequency display.

Makers of oscilloscopes, spectrum analyzers, frequency counters, power supplies and more testi equipment products

Project of receive only filters optimized for minimal loss and very high rejection of frequencies below 75% of the filter center frequency by K1TTT

Explore this high-resolution ITU Zones Map, a critical reference resource for amateur radio operators, international broadcasters, and telecommunications engineers. Originally established by the International Telecommunication Union – Radiocommunication Sector (ITU-R) Broadcasting Services Division (1999), this chart accurately divides the globe into 90 specific CIRAF zones. This authoritative visual guide is indispensable for planning High Frequency (HF) radio propagation, scheduling international broadcasts, and verifying locations for radio contests and awards. Distinct from the 40 CQ Zones, the ITU zoning system provides the official administrative framework used for global frequency management. This digitally enhanced version ensures maximum clarity of zone boundaries and numbering (e.g., Zone 28 for Central Europe), making it an essential tool for technical accuracy in logbooks and station management. It serves as a trustworthy standard for educators, hobbyists, and industry professionals alike.

A simple fixed frequency SSB voice transceiver for the 7 MHz amateur band

Ham radio frequency list consolidation software. The Ham Radio database can house a unlimited number of records. Holding frequency information from DC to Daylight. The Radio Scanner Database is designed to emulate a radio scanner. A 5,000 record table is provided and is organized by channel number.

An online javascript calculator for cubical quad antennas, simply input the resonating frequency to calculcate up to a five element quad antenna. This quad antenna calculator let you determine the total length of each element and spacing among elements.

Frequency allocation in Santa Barbara California