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The Olivia digital mode, a **Multi-Frequency Shift Keying (MFSK)** radioteletype protocol, is specifically engineered for robust communication under difficult propagation conditions on shortwave radio bands from 3 MHz to 30 MHz. Developed by Pawel Jalocha in 2003, Olivia signals can be decoded even when the noise amplitude exceeds the digital signal by over ten times, making it highly effective for transmitting ASCII characters across noisy channels with significant fading and propagation phasing. Early on-the-air tests by Fred OH/DK4ZC and Les VK2DSG on the Europe-Australia 20-meter path demonstrated intercontinental contacts with as little as one-watt RF power under favorable conditions. Common Olivia modes are designated as X/Y, where X represents the number of tones and Y is the bandwidth in Hertz, with examples including 8/250, 16/500, and 32/1000. The resource clarifies that Olivia, unlike some other digital modes, produces a constant envelope, allowing RF power amplifiers to achieve greater conversion efficiencies and making it less prone to non-linearity. Operators are advised that **Automatic Level Control (ALC)** can be set higher than no meter movement for MFSK modulation, as long as it's not driven past its high limit, contrary to common misinformation about other digital modes. The Olivia community encourages voluntary channelization on suggested calling frequencies, such as 14.0725 MHz for 8/250, to facilitate initial contacts, especially for signals below the noise floor. The Olivia Digital DXers Club provides links to Groups.io, Facebook, and Discord for community engagement and offers details on QSO parties.

The ICOM IC-R75, introduced in 1999, operates on 13.6 Volts DC and measures 241 by 94 by 229 mm. Its coverage spans from 30 kHz to 60 MHz, making it a versatile receiver for various bands. The review details available accessories, including optional filters and the **UT-106 DSP module**, which significantly enhances signal processing capabilities. Performance comparisons are drawn against other notable receivers such as the Drake R8B and earlier ICOM models, providing context for its audio quality and overall functionality. User feedback is integrated, offering practical insights into its daily operation and reception characteristics across the spectrum. This analysis offers an in-depth look at the IC-R75's technical capabilities and features, serving as a valuable reference for operators interested in this **legacy receiver**.

Join Kirk Pickering, K4RO, as he delves into the importance of calling CQ in amateur radio contesting. Learn about the debate over spotting assistance and why developing tuning and identifying skills is crucial for contest operators, especially newcomers. Discover valuable insights on how to enhance your contesting experience and maximize your success.

This resource presents a non-rigorous evaluation of the front-to-back (F/B) ratio of short Beverage antennas, specifically designed for low-band operation on frequencies such as 160, 80, 40, and 30 meters. The author, VE1ZAC, details the methodology used to measure the F/B ratio, which involves using a Millen Grid Dip Oscillator as a portable signal source. Measurements were taken by switching the antenna direction and recording S Meter and preamp readings to derive gain numbers. The document discusses the challenges faced in achieving accurate measurements and the assumptions made during the process, such as the calibration of S Meter units at 6 dB. This evaluation is particularly relevant for amateur radio operators interested in antenna performance on low bands.

The _Colorado QSO Party_ is scheduled for **September 12, 2026**. This amateur radio event focuses on contacts with stations operating within Colorado. The _Grand Mesa Contesters of Colorado_ sponsors the event. Operators may pursue contacts across all **64 counties** of Colorado. Activations for programs such as POTA and SOTA are permissible during the event period. Logs generated from these activations are eligible for submission to both the _Colorado QSO Party_ and the associated operating program. DXZone Focus: QSO Party | Colorado | Mixed | All Amateur Bands

The St Paul Island CY9C DXpedition is scheduled for August 26, September 5, 2024. All bands from 160-6 meters are planned.

Dates: Arrival: January 6th , Departure : January 21th 2023 Call sign: TN8K Operators - Petr OK1BOA, Petr OK1FCJ, Palo OK1CRM, Pavel OK1GK , Ruda OK2ZA, Ludek OK2ZC, Karel OK2ZI, David OK6DJ Bands: 160-6m + QO-100

This page provides a detailed comparison between the Zero Five and Gap Titan ham radio antennas. The author shares their personal experience with both antennas, highlighting pros and cons for each. They discuss aspects such as ease of assembly, customer service, tuning capabilities, performance on different bands, and the need for grounding and tuning. The comparison aims to help readers make an informed decision on choosing the best antenna for their needs, based on real-world usage scenarios and feedback.

Provides access to a robust DX cluster node, G6NHU-2, running DX Spider software, which facilitates real-time amateur radio contact spotting across HF bands. This service is engineered for high reliability and low latency, ensuring rapid dissemination of DX spots from a global network of interconnected nodes. It features multiple redundant links to prevent data loss and maintain continuous operation, even if individual connections drop. The cluster integrates directly with the Reverse Beacon Network (RBN), allowing users to enable or disable skimmer spots for specific modes like CW, RTTY, FT8, and FT4. It also offers an extensive one-year spot history, significantly longer than most other DX clusters, which typically retain only a month of data. The node supports various lookup commands for callsign information, beam headings, QSL routing, and FCC database lookups, enhancing operational efficiency for DXers and contesters. Additionally, it permits self-spotting, a feature increasingly relevant in modern contests, and provides detailed instructions for connecting popular logging software such as N1MM+, HamRadioDeluxe, MacLoggerDX, LOG4OM2, Logger32, and N3FJP's Amateur Contact Log.

Assessing the ICOM IC-R9000 communications receiver, this review details its operational parameters and user experience for radio enthusiasts. Introduced in 1985, the IC-R9000 covers a broad frequency spectrum from 0.1 MHz to 1999.8 MHz, making it suitable for a wide array of listening activities from medium wave (MW) to VHF/UHF. Key performance metrics include a dynamic range of **102 dB** with the narrow SSB filter, crucial for discerning weak signals in crowded bands, and its substantial physical dimensions of 424 x 150 x 365 mm and 20 kg weight. The receiver's architecture supports various modes, though it notably lacks synchronous detection, a feature often desired for improved AM reception under fading conditions. It incorporates 1000 memory channels and robust scanning capabilities, facilitating efficient monitoring across its extensive frequency range. This analysis provides insights into the IC-R9000's capabilities and limitations, offering a historical perspective on a significant piece of amateur radio and shortwave listening hardware.

This resource provides an in-depth look at Earth-Moon-Earth (EME) operating techniques specifically for the 432 MHz band and above. It outlines the differences in operational procedures between the 144 MHz and 432 MHz bands, emphasizing the importance of sequence lengths and scheduling. The initial calling period typically starts on the hour, with the eastern-most station calling first, which is crucial for effective communication. The document also discusses the challenges faced by operators, such as signal readability and the necessity of confirming exchanges. It highlights the significance of using a standardized procedure to enhance the likelihood of successful contacts. Additionally, it covers the use of signal reports and the importance of patience and clarity in communication, especially when dealing with weak signals. Overall, this guide serves as a valuable resource for amateur radio operators interested in improving their EME operations.

The author discusses ways to display VHF and higher bands using a K3/10 as  transverter, NooElec Upconverter, SDR, and SDR-Console. He observed that the results were remarkable, with the tuned frequency visible at +/-100kHz. The K3 Interface Option (KXV3A) produces a buffered IF output at 8.213MHz, which is received using a NooElec NESDR SMArt SDR dongle and Ham It UP Upconverter. The SDR-Console program is utilized, with Omnirig synchronizing the SDR and K3. To configure the system, particular parameters are required, such as adjusting the IF frequency to 133.213MHz (125MHz + IF frequency) and inverting the spectrum. The Panadapter demonstrated ES activity at 10m, and modest software tweaks may be required for improved performance.

This article discusses the Beverage antenna, a reception antenna for low bands, originally published in the Megahertz magazine between November 1990 and April 1991. It explains the challenges faced in receiving signals on low bands due to interference and how the Beverage antenna's directional radiation pattern can help improve reception of distant stations. The article highlights the importance of choosing antennas with low efficiency but sharp radiation lobes for better DX signal reception. It also compares the reception characteristics of signals from European stations versus DX stations, emphasizing the benefits of antennas favoring low arrival angles for DX signals on low bands.

IOTA: OC-003 activation planned for November 01 – November 15, 2024 Operation modes: SSB, CW, RTTY , FT8, FT4, PSK Bands: 160 – 6m, QO-100

This page discusses the construction and use of a low pass filter for MF/LF reception, specifically for the 630 meter and 2200 meter bands. The author, KA7OEI, shares technical insights and practical advice related to amateur radio, with a focus on improving reception in the low-frequency bands. This resource is useful for hams interested in building their own filters to enhance their MF/LF reception capabilities.

Demonstrates the construction of an active loop converter specifically designed for the Low Frequency (LF) bands, addressing common localized noise interference in LF reception. The design integrates a sharply tuned circuit and a tuned loop antenna, utilizing the loop as the sole tuned inductive element. By applying positive feedback, the converter significantly increases the loop's effective Q, achieving factors between 1000 and 2000, which sharpens tuning and reduces noise. The circuit employs an _NE602_ mixer stage, feeding its output to an HF receiver, with a crystal-locked local oscillator at 4 MHz. A 20-turn, 0.8-meter square loop antenna with 500 uH inductance is detailed, connected via 2 meters of figure 8 flex cable. The converter offers three selectable frequency bands: 195-490 kHz, 150-220 kHz (including the New Zealand amateur band), and 128-160 kHz (covering the European amateur band). Performance measurements indicate an effective 3dB bandwidth of approximately 100 to 200 hertz at 200 kHz. The article provides insights into component selection, including an _LF353_ op-amp and a trifilar wound transformer on a ferrite core. Sensitivity figures are presented, showing 7.5 uV of converted output per 1 uV/meter signal strength into a 50-ohm load, or 37.5 uV into an _FRG7_ receiver, highlighting its capability to extract weak signals from noise.

Learn about Amateur Television (ATV) on the 23 cm band (1240-1300 MHz) in this article from the September and October 2000 issue of Mégahertz magazine. Discover how ATV adds a new dimension to QSOs by allowing hams to visit stations, transmit real reports on antenna installations, follow signal paths on camera, and have simultaneous sound transmission. Explore the world of ATV experimentation, comparison, and innovation, made easier by existing equipment in many ham radio operators' homes. Find out about the ATV bands, bandwidth requirements, and the 23 cm band as a starting point for ATV activities.

Heltec Automation specializes in the production of _ESP32-based_ LoRa development boards, wireless modules, and gateways, catering to various amateur radio applications. The product line includes devices suitable for _APRS LoRa trackers_, Meshtastic nodes, and general long-range, low-power RF projects, providing hardware solutions for digital communication experimentation. The company's offerings support diverse wireless protocols such as LoRa, LoRaWAN, Meshtastic, and Wi-Fi HaLow, enabling users to build custom communication systems. Specific products like the _Wireless Stick Lite_ and various Heltec LoRa boards are designed for integration into DIY projects, facilitating rapid prototyping and deployment of wireless solutions. Heltec provides detailed product specifications, documentation, and community support, which assists hams in leveraging their hardware for packet radio, digital modes, and IoT applications within the amateur bands. The focus remains on versatile, programmable modules that bridge traditional amateur radio interests with modern wireless technology.

The XW4DX DXpedition website documents the amateur radio operation from Laos, a country ranked #98 on Clublog's Most Wanted list. This resource provides insights into the planning and execution of a significant DXpedition, including antenna choices like _Hexbeams_ at 14m, a 4-square for 40m, and a top-loaded vertical for 160m. The team, comprising operators such as _F4BKV Vincent_ and _F2DX Patrick_, focused on challenging paths, particularly towards the North American East Coast, where Laos is #41 most wanted. Operational constraints included prohibitions on 6m, 30m, 60m, and 80m bands within Laos, necessitating a focus on other HF frequencies, especially 160m and 40m. The expedition utilized up to five stations simultaneously, with equipment transportation being a major logistical challenge, partially mitigated by direct shipments from _Spiderbeam_ and donor support. The expedition ran from November 16th to 27th, 2023, with the complete XW4DX log uploaded to LoTW by December 23rd, 2023. This site serves as a historical record of their efforts to put Laos on the air for DXers worldwide.

Kilo Lima Radio Club is a global amateur radio community uniting operators across bands and borders.

The LICW Challenge is a daily event for ham radio operators, with special weekly on-air classes. It resets quarterly and covers bands from 160m to 2m, focusing on CW only. The event offers various point values based on member categories and bonus opportunities. Participants use specific calling frequencies and a CQ format to exchange information. Bonus points are awarded for specific criteria like contacts outside North America or special monthly members. The goal is to work as many LICW members as possible on different bands to earn points and bonuses.

Define the SWL contest 2026 as an event for monitoring a variety of languages on _medium wave_ (MW) and _shortwave_ (SW) AM radio stations. Participants can utilize either traditional radio receivers or _WEB SDR_ platforms to log their findings. The contest encourages the use of both analog and digital methods to maximize the diversity of languages captured. The contest rules specify that entries must include detailed logs of the stations received, including frequency, time, and language identified. Logs should be submitted in a standardized format to ensure consistency and accuracy in judging. The use of WEB SDR is particularly highlighted for its ability to access distant stations that may not be reachable with local equipment. The contest is open to all SWL enthusiasts worldwide, with a focus on European WEB SDR access. The event aims to foster a deeper understanding of global broadcasting patterns and linguistic diversity. Participants are encouraged to explore various bands within the MW and SW spectrum, enhancing their skills in signal identification and language recognition. The contest offers a unique opportunity to engage with the global SWL community and share insights into the art of listening.

Radio classifieds, technical articles, reviews and antenna designs for CB and Amateur bands.