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The Radio Reference Database for United States

Explains the fundamental principles of Software Defined Radio (SDR) and Digital Signal Processing (DSP) within the amateur radio context, serving as an initial entry point for hams interested in these technologies. It covers the architectural shift from traditional analog hardware to software-centric radio systems, detailing how digital signal processing algorithms are applied to modulate, demodulate, and filter radio signals. The resource compiles a list of external links to _white papers_ and project pages, offering further technical depth. This page provides a foundational understanding of SDR/DSP, enabling operators to grasp concepts like direct sampling and quadrature mixing. It references various projects and discussions, allowing users to explore practical implementations and theoretical underpinnings. The curated links direct users to resources that might cover specific SDR hardware platforms or software applications, facilitating deeper research into the subject.

A reference table of frequencies where you may find AM operations activity

The World of LF, by G3YXM reference site for longwave operations. Introduction to operating on 136 and 501 Khz

Provider of electronic components documentation. Offer a reliable tool to find semiconductors components technical information like parts, datasheets, cross reference, obsolete and new circuits.

The dbm online calculator and reference table for 50 Ohm

Homepage of the OS/2 and eComStation enabled Radio Amateurs, the HAM/2s. Reference site for OS/2 ham radio users,

Council Bluffs area Sheriff, Police, Fire, and State Police IOWA

Announces the retirement of Brand Electronics, a manufacturer specializing in **power meters** and various ham radio accessories, effective 2025. The company has served the amateur radio community for over 35 years, providing equipment for station setup and operation. The product line historically included accessories compatible with major transceivers from Icom, Yaesu, and Kenwood, alongside components and technical references for homebrew projects. Their offerings supported accurate RF power measurement, crucial for optimizing antenna systems and ensuring legal limit compliance. This notice serves as a final update regarding the company's operational status, marking the cessation of manufacturing and sales activities. The site provides no further details on product support or inventory liquidation.

Over 70 distinct contest rules are cataloged, including major events like the _ARRL DX Contest_, _CQWW DX Contest_, and numerous state QSO Parties, providing direct access to official guidelines. The resource also compiles contest calendars from sources such as _WA7BNM_, ARRL, and _LA9HW_, offering a centralized hub for upcoming operating activities. Historical contest records are detailed for various events, including _ARRL 10 Meter Records_ for W/VE and DX, _CQWW DX Records_, and _ARRL Sweepstakes_ results by K5KA. This compilation allows operators to review past performance and understand competitive benchmarks across different bands and modes, aiding in strategic planning for future contests. The resource serves as a practical reference for both casual participants and serious contesters.

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

Homebrewing a vhf bicone antenna with 8 clothes hangers and 4 feet of Sch40 non-metallic rigid conduit

The Tri-County CW Amateur Radio Club, operating under the callsign _W3TCW_, is situated in North Huntingdon, Pennsylvania, just southeast of Pittsburgh. This organization extends an open invitation to all licensed amateur radio operators, regardless of age or experience level, to participate in its activities and community. The club maintains a web presence detailing various aspects of its operations, including a calendar of events, a member roster, and contact information. It also provides resources related to _VE Testing_ and links to other local clubs and the _ARRL_ section website. Historical content, such as information from _Field Day 2008_, is also referenced.

Demonstrates the complete process of setting up a _HamClock_ for an amateur radio shack, utilizing a Raspberry Pi and the HamClock 4.21 software. The guide meticulously covers hardware recommendations, including specific Raspberry Pi models like the Pi 4, suitable SD cards, power supplies, and display options. It provides step-by-step instructions for preparing the SD card with Raspberry Pi OS, performing initial system updates, and executing the HamClock installation script. Detailed configuration steps are outlined for HamClock's seven setup pages, addressing callsign, grid square, DX Cluster settings (e.g., `dxspider.co.uk` port **7300**), map centering, and crucial features like automatic space weather map rotation and auto-upgrades. The resource further explains how to customize HamClock's display panels, such as replacing default panels with a large DX Cluster display or a dedicated Space Weather panel. It illustrates configuring the Live Spots panel to show _PSKReporter_ data, filtering spots by grid square and time (e.g., **15 minutes**), and selecting specific bands for monitoring. The author, G6NHU, shares personal preferences for map types, recommending the DRAP style with Robinson projection for optimal amateur radio utility. Additionally, the guide provides specific DX Cluster filtering commands to manage spot overload, including methods to exclude data modes like FT8 and FT4, ensuring a cleaner display of relevant DX activity.

This resource compiles claimed scores, often referred to as "rumor scores," for numerous amateur radio contests, providing a historical snapshot of competitive activity from 1993 through 2007. It lists entries for prominent events such as _CQWW CW_, _ARRL Sweepstakes_, _IOTA Contest_, and various _NAQP_ events, categorized by year and contest. Each entry typically includes the contest name and the month/year of operation, allowing users to quickly navigate to specific contest periods. The site also references the _3830 Web Page_ on Contesting.com as the primary submission portal for these claimed scores. The collection offers a unique perspective on contest participation and performance trends over more than a decade, preceding the widespread adoption of real-time score reporting systems. While not official results, these rumor scores provided early indications of top performers and overall activity levels for a wide array of HF and some VHF contests, including _ARRL 10M_ and _CQWW VHF_. The historical data can be useful for analyzing past contest popularity, identifying consistently strong operators, or simply reminiscing about earlier competitive eras in amateur radio.

The CQ World Wide DX Contest records page details the highest scores achieved in the CQ WW DX Contest across various categories and years. It systematically lists records for both SSB and CW modes, segmenting results by entry class such as Multi-Multi, Multi-Two, Multi-Single High, Multi-Single Low, Single Operator High Power, Single Operator Low Power, Single Operator QRP, Single Operator Assisted High, Single Operator Assisted Low, and Single Operator Assisted QRP. Each record entry specifies the callsign, the operator's callsign in parentheses if different, the year of operation, and the total score achieved. The data is further broken down by individual amateur radio bands, including 160m, 80m, 40m, 20m, 15m, and 10m, allowing for granular analysis of performance within specific frequency segments. The page also includes records for the "ALL" band category, representing cumulative scores across all operational bands. The presented records span from 1948 to 2025, providing a historical perspective on contest performance. This resource also references other CQ contests like CQ WPX, CQ WW RTTY, CQ WPX RTTY, CQ 160, CQ VHF, and WW DIGI, indicating a broader context of contest record keeping. It explicitly states that late logs are not included in the records, ensuring data integrity. The page is maintained by the World Wide Radio Operators Foundation, Inc.

A nice guide to make basic contacts in morse code with a particular reference to SOTA operations by VK3BQ

First released around 1995 and significantly redesigned as QWTelnet 2, this software provides a dedicated interface for monitoring DX-Cluster traffic via Telnet. It integrates a **SOTAwatch parser** with configurable audio alerts, allowing operators to receive notifications for specific search patterns in DX-Cluster remarks without constant screen attention. The application also supports parsing for **GMAwatch (German Mountain Award)**, providing alerts for German Mountain Award activations. QWTelnet 2.4.0, released on 07-APR-2012, runs on Windows (tested on W7) and is distributed as a ZIP file containing the `qwtelnet.exe` executable. It does not require a formal installation process; users simply extract and run the program. The software can display DX information for single bands, integrate with the Reverse Beacon Network, and link to external web resources for DXCC and SOTA information. It also supports local reference files for IOTA, WFF, and RDA awards, which users must source and place in the `qwtelnet/files` directory. For IOTA data, users can convert `IOTA.CSV` from UCX-Log or `DX4WIN_IOTA.TXT` into `iota.csv`. WFF and RDA reference files are directly sourced from their respective websites.

A complete guide for newcomers edited by the Radio Amateur Society of Australia Inc. This free PDF includes several basic articles for new hams, with particular reference to Australian regulations, but is however a good guide for those who are aproaching the hobby worldwide.

A large table wit properties of popular coaxial cables

Spectrum manufactures very high-performance, low-cost, GPS-disciplined time and frequency reference standards for industry, scientific, calibration, broadcast and amateur operators.

The "Shortish Guide to Using an Oscilloscope" elucidates the fundamental operation of oscilloscopes, detailing the purpose and function of vertical, horizontal, and triggering controls. It explains how vertical gain in Volts/cm and horizontal scale in sec/cm enable measurement of signal amplitude and timing, respectively. The resource differentiates between analog and digital scopes, noting that digital scopes often feature "soft" controls and are inherently storage scopes capable of capturing non-repetitive events. The guide dedicates a significant section to the critical role of oscilloscope probes, emphasizing their design to transmit waveforms without distortion or added noise. It explains the concept of a 10x passive scope probe, which reduces circuit loading by a factor of ten and eliminates waveform distortion through probe compensation, typically adjusted using a 1kHz square wave reference output. The document also provides practical advice on probe care and compensation procedures. Further sections address grounding considerations, explaining how a scope measures voltage relative to its chassis ground, which is tied to the protective earth. It offers troubleshooting steps for a blank screen and outlines essential good practices, such as checking input gain and probe attenuation, while explicitly warning against misusing probes or connecting the ground clip to mains voltage.

Rotatable Antenna with Phased Elements based on the orignal design concept of HB9CV antennas, is considered to have an higher gain than standard quad antennas. The Swiss Quad Antenna does not need any spreader or boom.

The W1HP Philips Amateur Radio Club, originally the Hewlett-Packard ARC, has a history rooted in Andover, Massachusetts, as an employer-sponsored club. It evolved from a "full-service" club to primarily a Field Day club, maintaining its focus on this major annual effort. The club has participated in Field Day under various configurations, including W1HP/1B in Arizona, and has partnered with K1KKM and utilized GOTA stations like K1KKM and KD1NA. Recent Field Day operations reflect adaptations to changing circumstances, with members operating individually due to COVID-19 and later under "new" ARRL rules, sometimes as a "distributed" club. The club's constitution is also referenced, providing insight into its foundational structure. This page is maintained by W1DYJ, with a last update noted as 9 December 2025.

9M6MU Alfons details his family's efforts to establish an independent, self-sufficient home at Eagle Plateau in Borneo, a 50-acre highland property. The resource highlights their integration of **solar photovoltaic panels** for power generation, alongside managing water supplies, organic gardens, and fruit trees. It covers the practical challenges and rewards of living off-grid, including maintaining power generators and addressing infrastructure needs, all while pursuing the hobby of amateur radio. The narrative emphasizes a holistic approach to healthy living and nature conservation, reflecting the family's aspirations for an ideal ham world. Alfons and his XYL Doris share their experiences in building shelter and antenna farms, showcasing their dedication to independence and sustainable practices away from the conventional grid. The site also references the Hillview Gardens Amateur Radio Club, suggesting community involvement.

A classic document originally presented in Proceedings of the Institute of Radio Engineers in 1937 and is, still today, the standard referenced by the FCC, text books and many amateur radio publications.

Amateur radio repeaters extend communication range for mobile and remote stations by retransmitting signals on a different frequency, often for emergency communications. The resource details various repeater bands, noting that 2 meters and 70 cm are primary for activity, with 10-meter repeaters offering potential national and overseas coverage. It specifies **18 channels** on 6 meters and **31 channels** on 2 meters, along with a new 70 cm offset of _7 MHz_ adopted in 2015. The content explains how repeaters can be linked via dedicated transmitters/receivers, landlines, or Internet VoIP systems like _IRLP_ and Echolink, enabling global connections. It also describes simplex gateways for multi-band operation and the use of CTCSS subaudible tones for access control and interference mitigation. The document highlights specialized repeaters for modes beyond voice, such as SSTV and ATV, particularly on 70cm and higher bands. Operational guidelines for efficient and courteous repeater use are referenced, along with links to Australian repeater listings and band plans.

Presents a historical timeline of amateur radio satellites, beginning with the inaugural _OSCAR 1_ in 1961 and extending through ARISSat-1 in 2011. It outlines the evolution of these orbiting transponders, initially simple battery-operated beacons, into sophisticated platforms supporting educational initiatives, emergency communications, and technology demonstrations. The document highlights the significant contributions of various AMSAT organizations and other entities in developing and deploying these spacecraft. Each entry provides specific launch details, including the date, launch vehicle, and initial orbital parameters such as apogee, perigee, and inclination. For instance, AMSAT-OSCAR 7 (AO-7) launched in 1974 into a 1459.00 x 1440.00 Km orbit, while AMSAT-OSCAR 40 (AO-40) achieved a highly elliptical 58665.00 x 1157.00 Km orbit. The resource also notes the allocated amateur satellite service frequencies, including 29 MHz (10m), 145 MHz (2m), 435 MHz (70cm), 1270 MHz (24cm), and 2400 MHz (13cm). The compilation serves as a concise reference for understanding the progression of amateur satellite technology and operations over five decades, showcasing the collaborative efforts of the global amateur radio community in space communication endeavors. It details the physical characteristics and project affiliations for many of the **20** satellites listed, providing a foundational historical context.

A photographic reference for wire and wireless telegraph key collectors and historians

The _DL4EBY_ resource page provides operational data for Earth-Moon-Earth (EME) communications on VHF, UHF, and microwave bands. It includes a 432 MHz and above EME Directory in ASCII and HTML formats. _K1RQG_ provides 432 MHz and up EME Net Notes. EME Operating Procedures were confirmed at the EME Conference 2002 in Prague. A lunar calendar from _DL7APV_ is linked via _G4CCH_'s pages. Resources for CW contest operation include the _PED411i.zip_ file. A "Cheat Sheet 432 & up" is available for EME operations. The _Dubus_ 70cm CW EME Activity Event is referenced for moonbounce activity. DXZone Focus: Operating Activity | Global | EME, CW | VHF, UHF, Microwave

UN Amateur Radio News, curated by Artur UN6QC, presents information relevant to Kazakh radio amateurs, including details on their account activity and participation in **WFF Kazakhstan** expeditions. The resource also documents various diplomas issued within Kazakhstan, such as those related to WFF Kazakhstan and special programs like the "50th Anniversary of the first manned space flight by Yuri Gagarin" and "The Columbus of the Cosmos" Award. It aggregates international ham radio news and maintains a calendar of international HAM competitions. The site, operational since May 14, 2010, serves as a central point for information on HAM competitions organized in Kazakhstan. It also references external resources like WWW.CQHAM.KZ for award details and WWW.EQSL.KZ for UN EQSL services. The platform aims to be a useful hub for both local and international amateur radio enthusiasts interested in Kazakh-specific operations and awards. Key events like the **UN DX Contest** and the First UN Field Day, held May 19-20, 2012, are highlighted.

Comprod Communications specializes in the design and manufacturing of RF communication solutions, including a comprehensive range of antennas, duplexers, multicouplers, and combiners. The resource details their product categories, which encompass base station antennas, mobile antennas, transit antennas, and disguised antennas, alongside mounting solutions and in-building systems. It highlights the company's 40-year history in adapting offerings to client needs and anticipating industry trends, emphasizing product durability and low maintenance for harsh environments. The company's offerings are presented as high-quality, designed to withstand extreme conditions from Arctic cold to equatorial heat and humidity. The site mentions solutions and technical sales support, training, and site analysis and system design as part of their service portfolio. It also references being a market leader trusted by over 1,000 customers worldwide, positioning itself as a partner for RF communication needs.

Amateur radio reference site in french managed by F4EZC

Listen to Ingham County Michigan Public Safety, County Sheriff, Police and Fire

HamAlert let you receive Push,SMS,Email notifications for Cluster,RBN,SOTAwatch spots, with customizable filtering based on many criteria including DXCC, SOTA and WWFF references, CQ zones

The _Nemos Photography_ blog presents a curated visual gallery focusing on _Morse keys_, offering a detailed photographic exploration of various telegraphy instruments. Each entry typically features high-resolution images of specific keys, highlighting their design, construction, and historical context. The content serves as a visual reference for collectors and enthusiasts interested in the aesthetics and mechanics of CW sending devices, often including close-ups of key components and unique features. This resource allows for comparative study of different key types, from vintage straight keys to modern paddles, without delving into technical specifications or operational performance. The emphasis is purely on the visual documentation of these artifacts, providing a unique perspective on the evolution and diversity of Morse key designs. It is a specialized collection for those who appreciate the craftsmanship and historical significance of telegraphy hardware.

Table reference for serial ports commands supported by TM-D700A

Presents the full owner's manual for the _Drake R-4C_ communications receiver, specifically a late version edition. This resource outlines the comprehensive operational instructions, covering everything from initial setup and tuning to advanced features and controls. Hams can reference detailed diagrams and explanations for proper signal reception across various amateur bands. The manual includes critical information for alignment procedures, ensuring the receiver performs to its optimal specifications. It details the steps required for calibrating the internal circuitry, which is essential for maintaining sensitivity and selectivity over time. My experience with vintage Drake gear confirms the value of these original documents for accurate adjustments. Furthermore, the document provides insights into troubleshooting common issues and performing routine maintenance. It serves as an authoritative guide for anyone operating or servicing this classic piece of amateur radio equipment, helping to preserve its functionality for years of DXing and ragchewing.

Summits on the Air South Africa formed in October 2002 to draw up an Association Reference Manual and compile a list of South African summits that can be activated or contacted for SOTA awards

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

Developing operational amateur radio equipment for the 134 GHz band presents significant technical challenges, particularly in frequency generation and stability. This resource details the construction of a 134 GHz system, outlining its architecture with separate transmit (Tx) and receive (Rx) modules, each employing a local oscillator (LO) and RF head units. The system utilizes a dual Flann 50 GHz lens-type horn antenna configuration for optimal signal coupling. The transmit path incorporates an LMX2541 synthesizer chip operating at approximately 2.8 GHz, referenced by a 10 MHz double-oven Morion OCXO for exceptional stability. This signal is multiplied through a series of stages (X4, then X2) to generate a 22.4 GHz signal, which subsequently drives a dual series diode multiplier to produce the final X6 signal for 134 GHz operation. The receive side features an anti-parallel diode mixer coupled to a 144 MHz transceiver via a preamplifier, ensuring effective downconversion. Operational mode is CW, achieved by keying a multiplier stage. The project includes images of the Tx and Rx head units and describes a successful 3.5 km test with G8ACE, demonstrating stable signal tones due to PLLs locked to OCXOs at both ends, confirming the system's robust performance.

Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.

_AT Auto_ is an automatic antenna tuner designed for amateur radio enthusiasts seeking efficient and reliable tuning solutions. This device automates the tuning process, allowing operators to focus on communication rather than manual adjustments. The tuner is compatible with a range of transceivers, enhancing its versatility in different shack setups. Its design incorporates advanced circuitry to ensure optimal performance across various bands. The _AT Auto_ tuner is particularly useful for those operating in HF bands, providing seamless transitions between frequencies. Its integration capabilities with other shack automation products make it a valuable component for modern amateur radio stations. The tuner supports multiple modes, including _SSB_ and _CW_, catering to diverse operating preferences. Its robust construction and user-friendly interface contribute to its appeal among both seasoned operators and those new to the hobby. Kessler Engineering's focus on innovation and quality is evident in the _AT Auto_'s design. The tuner is part of a broader product line that includes shack automation solutions, reflecting the company's commitment to enhancing amateur radio operations. Despite the website redesign, the tuner remains a key offering in their product portfolio.

The Pro 95 is a dual trunking handheld scanner designed by GRE and sold by Radio Shack

A 0-30 MHz step attenuator, constructed from switchable Pi attenuation pads, provides a practical tool for evaluating receiver sensitivity and calibrating S-meters. The design utilizes readily available 5% tolerance resistors, with values derived from paralleled components to achieve specific attenuation steps. A schematic (Fig 1) illustrates the circuit, including PCB pad shielding, while a table details required and actual resistor values, along with percentage differences. Measurements of voltage input versus output at various frequencies are used to calculate dB attenuation, presented in a graph (Fig 4). The resource includes formulas for determining output voltage from a known input and a comprehensive 0-40 dB voltage multiplier table, which is crucial for precise signal level management. The project also references external attenuator calculators and equations for further study. Photos (1-3) provide visual guidance for the assembled unit, showing bottom, top, and front views. The project emphasizes the use of **Pi attenuation pads** and **receiver sensitivity** evaluation, offering a hands-on approach to RF signal management.

The World Radiosport Team Championship (WRTC) is a unique on-site ham radio competition, typically held every four years, bringing together top operators globally. Unlike traditional contests where participants operate from their home QTH, WRTC competitors travel to a designated location and operate from identical stations under field conditions, ensuring a level playing field. Past events have taken place in diverse locations such as Seattle (1990), Slovenia (2000), Russia (2010), and Italy (2023), showcasing the international scope of this **radiosport** challenge. Because each WRTC event is organized by a dedicated, volunteer-driven committee, historical information and results often become dispersed across various online platforms. This resource serves as a centralized repository, diligently collecting and preserving data from all previous WRTC competitions. It provides a consistent point of reference for participants, enthusiasts, and researchers interested in the history and evolution of this premier **DX contesting** event. The WRTC Sanctioning Committee officially endorses this site, ensuring its accuracy and completeness.

The PG7V Contest Calendar provides a curated listing of significant **HF contests**, with a particular focus on events relevant to European amateur radio operators. It details contest specifics such as start and end times in UTC, eligible bands (e.g., 80 meters, 40 meters, 10 meters), and required exchange information (e.g., serial number, CQ-zone, DOK, locator, age). The calendar includes diverse modes like CW, SSB, PSK63, RTTY, and FT4, catering to various operating preferences. Featured contests include the RSGB 80m Club Championship, WW WPX Contest, IARU Region 1 Fieldday, and ARRL International Digital Contest. Each entry links directly to the official contest rules for detailed information. The calendar also notes specific participation rules, such as the 1 KHz QSY requirement in the HA3NS Memorial Contest or the 24-hour single-operator time limit in the ARRL International Digital Contest. This resource is updated regularly, ensuring timely information for upcoming **contest operations** over a four-week period. It serves as a practical tool for hams planning their contest activity.

The W6JWS 2-meter Repeater Maintenance and Repair Log documents the ongoing upkeep of a 146.745 MHz repeater, specifically addressing modifications to enhance its functionality. It details changes made to ensure the repeater powers up in _PL mode_ and to improve the reliability of touch-tone control, drawing comparisons to similar work performed on the AE6KE repeater. The log also notes a repair to a fused wire in the reverse battery protection circuit after an accidental polarity reversal, highlighting a temporary workaround where a wire was omitted but the system remained operational. The resource includes practical insights from Jeff Liebermann, AE6KS, regarding jumper configurations and programming, with accompanying photos. It provides access to several documents for the Icom RP-1510 repeater, including operating manuals and a schematic for the single logic board version, which differs from the dual-board configuration described in some printed manuals. The log mentions a specific modification to adjust the dropout delay, which was later deemed unnecessary, and references a related project for the AE6KE repeater, aiming to replicate successful modifications on the W6JWS machine, resulting in improved touch-tone reliability and proper PL mode activation.

A calibration kit useful when you need known reference impedances to properly calibrate your vector network analyzers.

A project by Don Wilhelm W3FPR