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A Primer for the new Packet Radio operator

Portable Vertical Antenna for 75m and 40m featuring Low radiation angle for DX, easy to install and to match 50 ohms

Great first time J-pole project. Covers most of the basics. This small and thin design also makes it good for several stealth applications.

A list of all IOTA reference numbers and IOTA groups for the Islands On The Air award, personalised to your own QTH

Download a 6 meter moxon antenna, drawings, photos, plots by Allen Baker KG4JJH, (10 Mb!)

The document discusses a two-element parasitic Delta-Loop array for the 40 meters band, aimed at radio amateurs interested in antenna projects. It provides detailed plans and instructions for building a homemade Delta-Loop antenna.

Freeware software that synchronize your PC's clock. Dimension 4 monitor your Internet connection and automatically adjust your PC's clock when you're online at an interval you specify. Windows version only.

A potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

Catalogs over 9,300 radio transmissions heard within Finland, providing a detailed frequency database for Finnish radio enthusiasts. The resource lists frequencies for various services, including maritime VHF channel 16 at **156.800 MHz**, RHA68 channel 16 at 71.100 MHz, and _MIL AIR_ frequencies like 251.100 MHz. It also documents air traffic control frequencies, such as 123.775 MHz for Area Control and 127.000 MHz for Approach Control, alongside frequencies for Finnish Air Force operations at 140.550 MHz. The database includes entries for commercial shared channels at 170.450 MHz and 458.250 MHz, as well as specific local business frequencies like 443.125 MHz for Sale Merimasku. Shortwave broadcast entries are also present, noting stations like BBC at 6.035 MHz from Tashkent and AIR Akashvani Ext.Sce at 11.900 MHz from Bangalore. The site organizes its extensive listings by categories such as "Liikenne" (Traffic) with 2397 entries, "Radioamatoori" (Amateur Radio) with 781 entries, and "Yle" (General) with 2305 entries. The database was last updated on 26.2.2024, reflecting ongoing maintenance and additions to its comprehensive collection of Finnish radio spectrum data.

A free to download and print, paper log sheet for shortwave listerners in PDF format.

Using moxon rectangles for WARC-Band antennas

N0KHQ Moxon rectangle for 17 meters, constructed from RG-58 coaxial cable

6m to 40m EndFed Half Wave Antenna project produces an inexpensive, multiband, end fed HF antenna matchbox that is quick and easy to setup and use.

Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

Interesting variant on the 3-element Yagi. Lightweight fiberglass (or similar) tubes supporting a wire structure of elements

ScanOhio Marine Radio frequencies

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

The article "Exploring the World of 10 Meter Beacons" by Ken Reitz, KS4ZR, provides an in-depth look at 10-meter beacon operations, focusing on their utility for propagation analysis. It details FCC Rules part 97.203 governing beacon stations, including license requirements, power limits (under 100 watts), and the specified band segment of 28.200-28.300 MHz for U.S. operations. The content highlights the diversity in beacon construction, from converted CB radios to home-brew QRP transmitters, and discusses the robust operating conditions these 24/7 stations endure. The resource presents several case studies of active 10-meter beacon operators like Ron Anderson KA0PSE/B, Domenic Bianco KC9GNK/B, and Bill Hays WJ5O/B, detailing their equipment, antenna setups, and typical signal report volumes. It also introduces the NCDXF/IARU International Beacon Project, which features 18 synchronized beacons worldwide transmitting on 28.200 MHz at varying power levels (100W, 10W, 1W, 100mW) to facilitate propagation testing. The article also covers the PropNet Project utilizing PSK31 on 28.131 MHz and the 250 Synchronized Propagation Beacon Project on 28.250 MHz. Practical advice for monitoring includes using the RST reporting method, understanding the impact of the solar cycle on 10-meter propagation, and tips for setting up a personal beacon, such as frequency selection and power output considerations. The IY4M Guglielmo Marconi Memorial Beacon Robot on 28.195 MHz is also mentioned for its automatic QSO mode. The article concludes with a list of other resources for 10-meter beacon information.

7 dB for 7 Bucks, a 2 meter beam antenna for the cost of a fast food meal!

A page with several coax cable characteristics comparison. Includes RG-316 RG-174 RG-58/U RG-59 RG-213/UBX RG-213 FOAM AIRCOM plus AIRCELL 7 ECOFLEX 10 ECOFLEX 15 H-155

ARRL pdf file on how remove car noise from your radio. Modern vehicles are RF noisy environments. Come learn how to identify and silence yor mobile noise sources, by WA6PDP

Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

Horizontal HF 6-Band turning arranging emitter with 2 elements Maria Maluca

An easy to build antenna for ground reception of NOAA weather or amateur satellite signals. Double cross antenna by Gerald Martes

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

Vox Recorder is a Windows utility wich allows recording sound from an audio source only when an audio signal is present; its main purpose is to avoid the recording of the silence eventually present at the input.

Stream is a software that implements MFSK16 and MFSK8 modes designed by me and Murray Greenman ZL1BPU. It also offers a series of experimental modes based on FEC, interleaving and several modulation techniques (PSK, QPSK, MSK).

Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site.

US Amateur Radio Band Plans by ARRL

Free Donwload of the PDF file of ITU and CQ zones of the world, made available by Icom America

Based on the N2PK design, this swr meter use a stockton directional coupler

Build your own home made Antenna Analyzer with an arduino micro, or a cheeper one with a pic processor

W5JGV antenna tuner for 150 - 500 Khz band

The ICOM IC-7300 is a cutting-edge HF transceiver that has garnered significant attention since its release. This review, published by ARRL in QST, provides an in-depth analysis of its features, performance, and usability. The IC-7300 is known for its direct sampling technology, which enhances its sensitivity and selectivity, making it a favorite among amateur radio operators. The review covers various aspects, including the user interface, audio quality, and overall operational capabilities, providing valuable insights for both new and experienced hams. In addition to its technical specifications, the review discusses the IC-7300's performance in real-world scenarios, such as DXing and contesting. It highlights the transceiver's ability to handle weak signals and its versatility across different modes. The review serves as a helpful guide for those considering the IC-7300 for their station, offering a balanced perspective on its strengths and potential drawbacks. Overall, this review is an essential resource for anyone interested in the ICOM IC-7300 and its place in the amateur radio landscape.

A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

Amateur Television (ATV) operations, particularly within the Arizona region, require dedicated resources for technical information, operational guidance, and community engagement. This club provides a focal point for hams interested in transmitting and receiving video signals on amateur bands. Members engage in local ATV repeaters, participate in technical discussions, and share knowledge on video modulation schemes, antenna designs, and station configurations. The club supports activities ranging from local simplex contacts to wider area repeater usage, fostering skill development in this specialized mode. The organization maintains a roster of club officers and offers membership opportunities to local amateurs. It also curates offsite links to other ATV resources, expanding the knowledge base available to its members and the broader amateur community. The club's emphasis on ATV helps propagate interest and technical expertise in a mode that combines traditional RF engineering with video technology.

A reference matrix of Kenwood Microphones by models with connector specifications and transceiver compatibilty.

Tombone VHF antenna for 146 MHz ad designed by YB8EIP

Summarizes a portion of the FCC rules 47 CFR 80.371(c) and 80.373(f)

Lets you listen to your scanner across your own network, or via the internet. Shoutcast/ICEcast compatible broadcasting for Uniden and GRE scanners. Broadcast your audio from your PC. ScannerCast is a specialized broadcasting solution that enables users to stream scanner audio feeds over the internet. This software supports both Uniden and GRE scanner models with tag information capability, while providing audio-only functionality for other scanners. Compatible with standard streaming protocols, ScannerCast allows remote listening via common media players without requiring specialized client software. The program features customizable tag display, adjustable bit rates, and seamless integration with Radio Reference. Its efficient design replaces multiple legacy applications while improving tag/audio synchronization. ScannerCast operates efficiently across various Windows environments, making remote scanner monitoring accessible from any location with internet connectivity. Scannercast is no more supported or developed by it's author.

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

Download chip64, freeware windows digital mode by IZ8BLY Nino

A 40 80 dipole antenna design by WA6ESC PDF File

MT63 soundcard program for Windows by IZ8BLY

30/17/12 and 20/15/10-Meter Tribanders and a 40 meters inverted V wire yagi antenna

W4RNL tutorial on on inductively coupled (link-coupled) antenna tuners

Put up the longest dipole you can fit, feed it with open wire line, connect it to the balanced output of your tuner and poof! Instant multiband antenna. Is life really that simple?

A two elements beam antenna tunable from 6 to 20 meters, based on the Maria Maluca antenna project by DB9EX, in german

Pre amplifier using a 2N5109 for the 160 meters band

Build a spiderbeam from scratch for 20-17-15-12-10 meters band