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This resource provides a historical listing of **unlicensed amateur radio beacons** active in the United States as of December 1993, specifically detailing both **LOWFER** (Low Frequency Experimental Radio) and **MEDFER** (Medium Frequency Experimental Radio) operations. The data includes beacon frequencies in kilocycles (Kc), identification codes, state locations, and the callsigns or names of the beacon operators. Frequencies range from 166.667 Kc for LOWFER to 1706.0 Kc for MEDFER, illustrating the spectrum utilized by these experimental stations. The information was originally compiled by Mark Burkart and relayed to the rec.radio.shortwave newsgroup by Rick Robinson, KF4AR. The list serves as a snapshot of experimental beacon activity from the early 1990s, offering insight into the types of operations and the individuals involved in unlicensed, low-power transmissions. It highlights specific beacon IDs like "ABC SC" on 510.5 Kc and "GK HI" on 1620 Kc, alongside operator details such as Todd Roberts (WD4NGG) and Herb Vanderbeek (WY6G). While not a current operational guide, it is a valuable historical document for those interested in the evolution of LF/MF experimental radio and the early days of internet-based amateur radio information sharing.

This article addresses the subject of obtaining the best signal transfer from an antenna to the typical 50-ohm receiver input over a wide frequency range, with emphasis on medium-wave (500 - 2000 kHz), encompassing the standard AM broadcast band and the 160-m amateur band.

WiNRADiO for Mac, WiNRADiO provides Apple Macintosh support for our most popular receiver, the WR-1550e, a medium-range external receiver with frequency range 150 kHz to 1.5 GHz

Differential Global Positioning Service (DGPS) is a land-based augmentation system that receives and processes signals from orbiting GPS satellites, calculates corrections from known positions and broadcasts these corrections via a Medium Frequency (MF) Transmitter to DGPS users in the Broadcast Site's coverage area.

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.

Radiowave propagation in the medium and high frequency spectrum in DOC format

Mark Connelly, WA1ION article on Medium Frequency Amplifier Circuits in PDF format, include some RF amplifier schematics

SPX Communication Technologies, operating under the TCI International brand, presents a range of radio frequency (RF) solutions primarily for government, defense, and commercial sectors. The offerings include advanced systems for spectrum monitoring, communications intelligence (COMINT), and high-frequency (HF) and medium-frequency (MF) broadcasting and communication antenna systems. Specific product lines encompass _Blackbird_ COMINT systems, _Scout_ spectrum monitoring receivers, and various antenna arrays designed for robust performance in challenging RF environments. The resource details the capabilities of these systems, such as wideband signal detection, direction finding (DF), and signal analysis, crucial for intelligence gathering and regulatory compliance. It also highlights the engineering behind their antenna designs, which are optimized for specific frequency ranges and operational requirements, including high-power broadcast applications and secure military communications. The information presented emphasizes the integration of hardware and software for comprehensive RF situational awareness. The company's focus on empowering partners to "Command the Spectrum" underscores its commitment to delivering critical tools for signal interception, analysis, and management across diverse operational landscapes.

The New England Historical Radio Society Inc. is an organization dedicated to the preservation of commercial Morse Radiotelegraphy on medium and high frequency.

A medium power End Fed Half Wave Antenna coupler, specifically tuned to the QRP frequency of 7030 kHz. Constructed from coil stock and capacitors, it achieves an impedance ratio of 64:1. The coupler has proven effective for power ranges from 2 to 100 Watts on the 40m band.

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.

The **Yaesu FRG-100** shortwave receiver, introduced in 1992, operates across a frequency range of 50 kHz to 30 MHz, accommodating AM, LSB, USB, and CW modes, with an optional narrow-band FM capability. Its physical dimensions are 238 x 93 x 243 mm, with a weight of 3 kg, making it suitable for both portable and fixed station deployments. Power options include standard mains voltage or 12VDC, providing operational flexibility for diverse listening environments. The front panel integrates a manual tuning knob, an analogue signal strength meter, and an LCD display that provides critical information such as frequency, operating mode, memory channel, and time. Users can configure various operational parameters, including tuning steps and bandwidth filters, to optimize reception for specific signals. This review highlights the FRG-100's straightforward interface and its utility for shortwave listening enthusiasts. The design emphasizes user-friendly adjustments for settings, which contributes to its appeal among those interested in general coverage reception.

Examines the Sangean ATS-505 portable receiver, a unit introduced in March 2000, providing an in-depth analysis of its capabilities. The review details critical specifications such as its 6 Volt DC power requirement, utilizing 4 AA batteries, and its physical dimensions of 128 x 214 x 39 mm, weighing 840 g without power cells. Frequency coverage spans **LW** from 153-279 kHz, **MW** from 520-1710 kHz, **SW** from 1711-29999 kHz, and FM from 87.5-108 MHz, making it a versatile listener for various broadcast types. Key features highlighted include a backlit display for low-light operation, 45 memory presets for quick access to favorite stations, and the inclusion of Single Sideband (SSB) mode, which is crucial for serious shortwave listening and utility monitoring. The review also draws technical comparisons with other Sangean models, specifically the ATS-404 and ATS-909, pointing out differences in band coverage and operational features. This independent assessment offers practical insights into the ATS-505's performance, helping enthusiasts understand its place within the portable receiver market.

Examines the AOR AR-7030 communications receiver, detailing its technical specifications and operational characteristics. The resource describes its compact design, CNC machined aluminum cabinet, and a frequency range spanning 0-32 MHz. Key features include a ceramic metal cased 4 kHz AM filter, with typical bandwidths of 2.2 kHz, 4.0 kHz, 5.3 kHz, and 9.5 kHz, alongside 400 memory channels and multi-timer functionality. It emphasizes the receiver's high-quality components and a design philosophy focused on reliable performance without superfluous features, making it a dedicated tool for serious listeners. The review assesses the AR-7030's performance within its price class, particularly for **medium wave** and **shortwave** reception. It provides insights into how the receiver's design choices, such as its robust construction and specific filter options, translate into practical listening experiences. The analysis highlights its suitability for users prioritizing signal clarity and operational stability over extensive, complex features, offering a clear perspective on its utility for dedicated DXers and broadcast listeners.

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.

Demonstrates the conversion of an _Elecraft K2_ QRP HF transceiver to serve as a 2-meter Intermediate Frequency (IF) rig for microwave transverters, addressing the obsolescence of older _Yaesu FT-290R_ units. The project integrates a _DEMI 144-28DC_ transverter board, configured for a 28 MHz IF, and details the necessary modifications to the K2, including the installation of the K160M module for a separate receive-only antenna input and the KSB2 SSB module for voice operation. The modified K2 provides a stable 1-watt output for the 2m IF, utilizing the QRP antenna jack for transmit and the K160M input for receive, with a custom PTT control circuit. The article outlines the physical integration and electrical interfacing, including the design of an internal attenuator for the 28 MHz IF output and a control circuit for the 144 MHz interface. It also covers the construction of a medium power amplifier using an _MGA-31389 MMIC_ to boost the 2m output to 100 mW, matching the original FT-290R performance. Performance measurements for the amplifier, including output power versus input power and gain versus frequency, are presented. The project culminates in a fully integrated solution, with schematics and photos illustrating the internal wiring and external connectors. The modified K2, dubbed the "K290R," was successfully deployed in the 2017 _ARRL 10 GHz and Up Contest_ with a _Kuhne 10 GHz_ transverter, demonstrating reliable operation for CW and SSB modes.