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Signalprocessing for SSB - Direct Conversion Receiver using Phasemethod for Sideband Supression, does all necessary signalprocessing for Direct conversion Receivers using IQ-mixer for demodulation.

Presents the detailed construction of the _FLA25HV_ antenna, a specialized array optimized for Earth-Moon-Earth (EME) communications on the 2-meter band. This resource provides schematics and practical insights into building a high-gain antenna system capable of reflecting signals off the lunar surface, a challenging but rewarding aspect of amateur radio. It covers the mechanical and electrical considerations essential for achieving the precise pointing and signal strength required for successful moonbounce contacts, often yielding **20 dB** or more gain. Amateur radio operators pursuing EME operations require robust antenna systems and precise tracking capabilities. The FLA25HV design addresses these needs by focusing on element spacing, impedance matching, and structural integrity to withstand environmental factors while maintaining critical alignment for lunar reflections. Such systems are crucial for making contacts over distances exceeding **768,000 km**. This personal page serves as a practical guide for hams interested in constructing their own EME arrays, offering a glimpse into the technical dedication involved in pushing the boundaries of VHF/UHF propagation.

RigPix front and back side pictures of the Yaesu FT-450

Free windows basic and simple CAT program specifically for the Yaesu FT-857 radio. It provides an unlimited memory storage area which resides on the client side.

Constructing a functional spectrum analyzer for the 0-100 MHz range presents a significant challenge for radio amateurs, often requiring specialized components and careful calibration. This project details a homebrew spectrum analyzer design utilizing common integrated circuits like the _SA605D_ FM receiver IC and _MAR-6_ MMIC amplifiers, aiming for a cost-effective solution. The design incorporates a low-pass filter, RF amplification, a voltage-controlled oscillator (VCO) for downconversion, and multiple IF stages at 150 MHz and 10.7 MHz, with a resolution bandwidth (RBW) of 15 kHz. Critical components such as the _SBL-1_ mixer and varicap diodes are specified, alongside instructions for winding inductors and tuning filters. The analyzer's performance is discussed in terms of input level limitations, specifically the 1dB-compression point and third-order intercept point, to ensure accurate measurements and prevent component damage. The _SA605D_'s logarithmic Received Signal Strength Indicator (RSSI) output serves as the detector, driving the Y-input of an oscilloscope, while a _TL084_ op-amp generates the sweep signal for the X-input. Potential enhancements include adding a step attenuator, improving front-end filtering, and implementing switchable IF filters for variable RBW, allowing for greater versatility in analyzing RF signals.

The QRP choke balun described utilizes a high permeability ferrite rod and RG-174 coax, aiming to present high impedance to common-mode currents across the HF spectrum. The construction involves winding as many turns of RG-174 as possible around the ferrite rod, then encapsulating the assembly with hot glue. This design prioritizes maximizing inductance to suppress unwanted shield currents, particularly in unbalanced antenna configurations. While the balun's effectiveness is subjectively reported as good, a potential design consideration involves the dielectric properties of the hot glue. This material could increase turn-to-turn capacitance, potentially reducing the balun's performance at higher HF frequencies, though this specific aspect has not been formally tested by the author, _AA5TB_. The project serves as an illustrative example of a practical, junk-box construction rather than a rigorously engineered solution. Photographs detail the evolution of the balun, from the initial winding process to its integration within a _B&W dipole center insulator_ and final camouflaged assembly.

There is considerable confusion about the various types of baluns, this article try to make it clear.

This project will enable you to build a monoband long wire inverted vee with 3/4 wave length sides that will have a bit of gain

A portable 4 elements quad antenna for 144 MHz, 9 to 10 DBd forward gain, 30 DB front-to-back ratio, and 33 DB front-to-side ratio

One popular rumor or thought is that antenna gain doubles every time we double the number of elements

Demonstrates the design and construction of a 9-element Yagi antenna for the **70 cm band** (432 MHz), based on the DK7ZB concept. The resource details EZNEC+ calculations for a single antenna, providing gain, sidelobe suppression, and front-to-back ratio figures. It also presents a comprehensive analysis of stacking two such antennas, including optimal stacking distance (1000 mm) and the resulting performance enhancements for the stacked array, such as an increased gain of 17.03 dBi. The article includes detailed drawings, wire file dimensions in millimeters, and azimuth/elevation plots for both single and stacked configurations. Practical construction steps are documented with original photographs, illustrating element mounting, the **28 Ohm matching system** using two quarter-wave 75 Ohm transmission lines, and the critical N-connector wiring. It also covers the iterative process of fine-tuning the driven element length to achieve a return loss of 20 dB, validating the EZNEC+ simulation results with actual measurements.

OM International sideband society incorporated nets 75M, 40M, and 20M Nets begin one hour earlier during Daylight Savings Time

QRPPAL, developed by WB2QAP, functions as a freeware QRP logging application for Windows 3.1 and Windows 95, initially introduced at the 1996 Dayton Hamvention FDIM QRP symposium. The software integrates the original "Logger" program, which was specifically designed for ARCI contest dupe checking and logging, alongside versions tailored for NW-QRP, MI-QRP Club, and Colorado QRP Club contests. It is distributed as a self-extracting archive, _qrppal!.exe_, approximately 1.2 MB in size, which unpacks _qrppal.exe_ and _setup.exe_ for installation. The program's modular design incorporates extensive QRP-centric databases, covering ARCI awards, QRP club listings, QRP periodicals, kit/vendor directories, and detailed rig reviews, often with photos. Noted reviewer Bob Gobrick, _VO1DRB_, described it as a "QRP Internet Web Site in a box" due to its comprehensive data modules, which are also user-modifiable. Installation involves running _setup.exe_ to create batch files like _setup95.bat_, which then establish a c:\qrppal directory and deploy the program files. Users initiate the application by typing "qrp pal.tkn" after setup. The Colorado QRP Club contest version should be avoided due to specific first name exchange requirements not supported by that module.

For radio amateurs seeking compact and efficient antenna solutions, particularly for restricted spaces or noise reduction, HF loop antennas present a viable option. This resource compiles several articles from the ARRL, detailing the theory, design considerations, and practical construction of various loop configurations. Topics include small transmitting loops, receiving loops, and multi-band designs, often emphasizing their performance characteristics such as directivity, bandwidth, and impedance matching. The collected articles provide insights into the comparative performance of different loop geometries, such as circular versus square loops, and discuss the impact of conductor size and tuning methods on efficiency. Practical applications are explored, including their use in portable operations, stealth installations, and urban environments where noise mitigation is critical. The content often includes construction diagrams, parts lists, and performance data derived from modeling or field tests, enabling hams to replicate or adapt the designs for their specific operating conditions.

Demonstrates the product line of _LZ Antenna Ltd._, a Bulgarian manufacturer specializing in amateur radio antennas and custom electronic devices. The company focuses on robust, high-quality HF multiband Yagi and vertical antennas, leveraging over 20 years of experience from founder Georgi Georgiev in radio amateur development. Featured models include the LZA 8-4, LZA-10-3, and the LZA-7-3A WRTC 2022, alongside various rotary dipoles like the LZA1 40/30m. Provides specifications for several Yagi antennas, such as the LZA-9-5, LZA-13-7, and LZA-6-3 (a 6-element, 3-band design). The company emphasizes applying "leading edge technology" to high-frequency communication equipment production, with products designed for durability and performance. The LZA-10-5 Yagi offers **12.5 dBi** gain on 10m, while the LZA-13-7 provides **13.2 dBi** on 20m, showcasing competitive gain figures for DXing and contesting.

QSL card printing tool for windows, can print complete back side of the QSL card and also labels

Presents a construction project for a linear-loaded 40-meter rotatable dipole, detailing the design evolution from mid-element coils to 300-ohm twinlead loading. It covers material selection, including repurposed fishing poles and EMT conduit, and outlines the assembly process for the antenna elements and mounting plate. The resource provides specific measurements for element lengths and linear loading sections, along with SWR plots demonstrating the antenna's resonance at 7.035 MHz with a 1.1:1 SWR, and bandwidth up to 7.120 MHz below 2:1 SWR. The article documents the antenna's performance during various RTTY and CW contests, including the SARTG RTTY and SCC RTTY contests in August 2006, and the ARRL DX CW and CQWW WPX RTTY contests in February 2007. It reports successful operation at 500-1000W, noting improved performance after replacing a faulty coax cable. Specific DX contacts from British Columbia, including stations in Europe and South Africa, are listed, illustrating the antenna's capability despite its shortened length and relatively low height of 55 feet. The content highlights practical considerations such as weatherproofing the connections and supporting the fiberglass elements to prevent sagging. It also includes a brief comparison to an inverted-V at similar height and a ground-mounted vertical, noting the rotatable dipole's quieter reception. The author shares insights into the iterative design process and tuning adjustments made to achieve optimal resonance.

There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.

With over 20 years of experience, Proyecto 4 operates as a specialized ham radio retailer in Madrid, Spain, providing a diverse inventory of transceivers, antennas, and related accessories. The store features popular models like the _ICOM IC-705_ and _ICOM IC-7300MK2_, alongside Yaesu transceivers such as the _FTX-1 Optima_, which delivers 100W on HF and 50W on V/UHF bands. The product range includes mobile and portable antennas, such as the D-Original DX-NR770HB, offering 3 dB gain on 144 MHz and 5.5 dB on 430 MHz, and the Diamond RH-770 with a BNC connector. CB radio enthusiasts can find the Anytone CB SMART II AM/FM transceptor and the Telecom LS145 mobile antenna, rated for 500W and 4 dB gain on 26-30 MHz. Proyecto 4 emphasizes its in-house technical service, inviting customers to visit their laboratory for repairs and technical consultations via sergio@proyecto4.com. The store also highlights customer reviews and offers promotions like Yaesu Cashback, providing savings up to 100€.

Presents the design and performance of a 4-element wire Yagi antenna for the 40-meter band, building upon VE3VN's earlier 3-element switchable wire Yagi. The resource details the antenna's evolution, highlighting the transition from a 3-element to a 4-element configuration and the resulting improvements in gain and front-to-back ratio. It provides specific insights into the antenna's construction and expected operational characteristics. VE3VN shares insights from field results, noting the antenna's performance on 40 meters. The discussion includes the antenna's pattern and matching characteristics, crucial for any DXer or contester looking to optimize their signal on this popular HF band. The author's experience with the previous 3-element design informs the enhancements made to this 4-element iteration. The article includes a visual representation of the antenna's current view, offering a practical perspective on its physical layout. It serves as a valuable reference for hams considering a directional wire antenna for 7 MHz operations, demonstrating a practical approach to achieving enhanced directivity and gain.

The 11-meter band, often associated with Citizens Band (CB) radio, presents unique challenges and opportunities for long-distance communication, particularly for operators interested in DXing. This group facilitates discussions and information exchange among enthusiasts who operate on this frequency, often utilizing single-sideband (SSB) modulation for improved range and signal clarity compared to traditional AM CB operations. The community provides a platform for members to share experiences, technical insights, and propagation reports relevant to 27 MHz operations. Members engage in discussions covering various aspects of 11-meter DX, including antenna configurations, transceiver modifications, and operating techniques to maximize signal propagation across continents. The forum serves as a central hub for coordinating contacts, sharing QSL information, and celebrating successful long-haul QSOs. Specific topics often include optimizing power output, reducing noise, and understanding solar cycle effects on 27 MHz. The group's activities extend to organizing virtual gatherings and promoting ethical operating practices within the 11-meter DX community. It supports both seasoned operators and those new to the band, fostering a collaborative environment for exploring the capabilities of CB radio beyond local communications.

This resource, "Transistor Audio Preamplifier Circuits," offers comprehensive design guidelines for constructing **bipolar transistor** audio preamplifiers. It delves into critical aspects such as quiescent current setting, voltage gain calculation, and the impact of various component choices on circuit performance. The content provides several _schematic diagrams_ illustrating different preamplifier configurations, including single-stage common emitter and two-stage designs, alongside explanations of their operational characteristics and practical implementation considerations. The analysis extends to frequency response, noise performance, and distortion, providing insights into optimizing these parameters for specific audio applications. The resource presents calculated gain figures for various stages, demonstrating how to achieve desired amplification levels. It also discusses the importance of proper power supply decoupling and input/output impedance matching, crucial for integrating these preamplifiers into larger audio systems or ham radio transceivers. The practical application of these designs is evident in their suitability for microphone preamplifiers or general-purpose audio amplification.

Quad and loop antennas comparisons, evaluating the impedance and gain of both antennas and considerationso n horizontal loop antennas for low bands by PA0FRI

Demonstrates the design and construction of a compact, portable multi-band mini-delta loop antenna, specifically optimized for /P (portable) operations from remote locations like Scottish islands. The resource covers the theoretical underpinnings of half-wave loops, contrasting closed and open configurations, and then details the application of a folded dipole principle to achieve a 50-ohm match for direct coax feed. It presents empirical formulas for calculating element lengths, considering the velocity factor of common wire types, and provides a detailed example for a 20m (14.175 MHz) version. The article includes a comprehensive table of dimensions and allowances for a five-band (20m, 17m, 15m, 12m, 10m) mini-delta beam, along with construction hints for the central support and balun. It specifies a 1:1 trifilar balun wound on a ferrite rod and describes the antenna adjustment process using an _MFJ-259B Antenna Analyser_. Initial test results indicate an SWR of 1:1 at resonance and a bandwidth of approximately 240 kHz on 20m, even at a low height of five feet above ground. The distinctive utility lies in its focus on a practical, easily deployable beam antenna for portable DXing, offering a viable alternative to more complex or larger arrays.

The Voice of America (VOA) website serves as a primary digital platform for its international news and information services, broadcasting in 44 languages. The resource presents a wide array of current events, geopolitical analyses, and cultural reports, reflecting a global perspective on news originating from the United States. Content spans various regions, including Africa, Asia, the Middle East, and specific country-focused reports from VOA's language services, such as VOA Uzbek, VOA Kurdish, and VOA Russian. The site features top stories, special reports, and sections like "All About America" and "VOA Explains," providing in-depth context on US-related topics and global issues. The VOA platform offers a continuous stream of updated news articles, covering political developments like government shutdowns, diplomatic relations, and international conflicts, alongside social and economic issues. It also includes sections for "Worth Watching" videos and "From VOA's Language Services," highlighting the breadth of its multimedia output. The content is designed to inform a worldwide audience, often presenting multiple perspectives on complex international events and US foreign policy, making it a significant reference for those monitoring global news and shortwave broadcast content.

Presents a dynamic, searchable database of shortwave broadcast schedules from around the world, enabling users to locate active stations or plan listening sessions based on scheduled transmission periods and frequencies. The resource details specific station names, such as _Radio Habana Cuba_, _Deutsche Welle_, and _All India Radio_, alongside their operational times and assigned kilohertz frequencies. It also incorporates a distance calculator, which leverages geographical coordinates to estimate propagation paths, though it notes occasional data inaccuracies leading to transmitters appearing in oceanic locations. The platform's development log highlights continuous updates, including the integration of new seasonal schedules like "A24 frequencies" and "B23 schedule," reflecting the fluid nature of shortwave broadcasting. It documents challenges with geolocation services, particularly concerning Google API changes that impacted distance calculations and required user-side browser configuration adjustments for optimal functionality. The site owner, VAXXi, frequently communicates these technical adjustments and database updates, often acknowledging user contributions and donations. Distinctively, the resource provides a historical perspective through its update archives, illustrating the evolution of shortwave listening over more than a decade since its inception in 2011. It also mentions specific events, such as the BBC adding shortwave broadcasts for Ukraine on 5875 kHz and 15735 kHz, demonstrating its responsiveness to global events impacting broadcast schedules. The site's commitment to user feedback is evident in its bug reporting and feature request mechanisms, contributing to its ongoing refinement.

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.

Since February 2002, 3830scores.com has served as a central repository for amateur radio contest score rumors, allowing contesters to quickly post and view claimed scores and comments. The platform facilitates the sharing of **claimed scores** for numerous contests, including the ARRL DX Contest, CQ WPX RTTY Contest, and various QSO Parties. Users can access submittal forms for current and recent contests, with options to define and save default form values for efficiency. The site also provides links to the 3830 Reflector, where submissions are posted, fostering immediate community engagement regarding contest performance. Summaries of all submitted scores are instantly available, offering line scores, **band/mode breakdowns**, and compilations of operator comments. Historical summaries for major contests extend back to 2002, with all contest data accessible from 2007. The platform includes a search function to locate all postings associated with a specific call sign and a 'Compare Scores' feature, enabling side-by-side analysis of multiple calls across different contest editions or a single call's performance over several years.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Analog circuit simulator for Windows (not a SPICE). A great tool for students, amateurs, as well as for experienced engineers. Free Demo.

Homebrew a cobwebb antenna for the HF bands. This page describe a cobwebb multiband antenna resonating on 14 18 21 24 and 28 MHz. The cobweb antenna model can be considered a fan dipole, or better, multiple dipoles fed in parallel.

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cables. Many hams connect the center conductor of the coaxial cable to one side of the dipole, and the shield to the other. Wrong!

A J-pole antenna plan made using a half inch copper tubing

Information about pirate radios, what they are and why are considered pirates

Details Guglielmo Marconi's foundational contributions to radio communication, highlighting his 1898 Patent **7777** which introduced tuning circuits for independent simultaneous communications. Chronicles the historic transatlantic reception of the Morse code letter 'S' on December 12, 1901, from Poldhu, Cornwall, to St. John's, Newfoundland, a distance of over _3,500 kilometers_. The exhibit showcases early Marconi 10-inch spark transmitters, identical to those used on the _Titanic_, alongside Canadian Marconi crystal detector models. It also features high-end commercial receivers like the IP501, weighing **87 pounds** and originally priced at $595.00, demonstrating the robust construction and technological advancements of the era.

An inverted Vee antenna calculator that consider also minimun vertical height and horizontal spread by M0UKD

Some antenna manufacturers place baluns at the incorrect location in LPDA arrays. If we consider what the balun does we can see how the mistake occurs.

Paddles made from readily available materials, like double sided PC board material and cost almost nothing to build.

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

Receiver converter that can be plugged to the backside of the Yaesu FT-817 battery powered portable transceiver

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

The HB9DHG Contest Calendar aggregates contest information, offering direct links to official rules and past results for various amateur radio competitions. It features a curated list of events, with a focus on HF and digital mode contests, ensuring that operators can quickly access relevant details for upcoming and historical events. The calendar is regularly updated to reflect the latest contest schedules and rule changes. Each entry typically includes the contest name, dates, and a direct link to the sponsoring organization's page, such as ARRL or DARC, where full regulations and scoring information are available. This resource streamlines the process of finding contest specifics, which is crucial for effective pre-contest planning and post-contest analysis. Validation and checking of contest information are emphasized, providing a reliable source for operators planning their contest activity throughout the year. The calendar supports both CW and SSB modes, alongside various digital modes.

An easy to deploy antenna, commonly considered the best solution for portable operations. Thir article includes a simple LC parallel circuit to match the impedance by IW7EHC

The Resonant Feedline Dipole (RFD) HF antenna design utilizes a single piece of coaxial cable and a stranded wire section, forming a 1/4-wavelength radiator. This configuration, based on a 1997 ARRL Handbook design (page 20.17), functions by RF traveling on the inside of the coax shield and returning on the outside, creating the second half of the dipole. A choke wound into the feedline prevents RF current from flowing back down the feedline. Construction details include using RG-58a/u coax for a 75m version, with a 1/4-wavelength section of stranded wire soldered to the center conductor. The document provides choke dimensions for RG-213, RG-8, and RG-58 coax across 3.5 MHz to 28 MHz, specifying cable length and number of turns. Dipole dimensions are also tabulated for frequencies from 3.6 MHz to 28.4 MHz, listing overall length and individual leg lengths. Field tests included deployment near Bryson City at 5 feet off the ground and as a sloper during WCARS Field Day in Asheville, yielding successful local and regional contacts.

Hjemmesiden til Follogruppen av Norsk Radio Relc Liga

TurboLog is a station management and logging program designed for amateur radio operators, providing robust database and logging functionalities. It features fully integrated support for controlling typical radio station equipment, including transceivers, packet radio TNCs, Morse and voice keyers, and digital mode terminals. The software also incorporates antenna switching capabilities and acoustic alerting, streamlining station operations for DXing and contesting. The program's utility extends to award tracking for entities like DXCC and IOTA, alongside comprehensive callbook and ham database integration. It supports log import and export, QSL label generation, and includes TNC drivers for packet radio. The trial version allows users to evaluate its extensive features before commitment, making it a versatile tool for managing complex amateur radio station configurations and operational data.

This antenna is designed to be mounted off the side of a tower. Works on 136-153 Mhz range but also on 70 cm band

Presents a QRP AM/CW transmitter project specifically designed for the 10-meter band, utilizing a crystal oscillator and a collector-modulated AM oscillator. The design employs a 2N2219(A) transistor in a Colpitts configuration, generating 100 to 350 mW of RF output power depending on the 9-18 Volt supply voltage and modulation depth. Frequency stability is maintained by a 28 MHz crystal, with fine-tuning possible via a Ct1 trimmer capacitor for approximately 1 kHz adjustment. The resource details the RF oscillator stage, implemented with a 2N2219 NPN transistor, emphasizing frequency stability and low power dissipation. It also covers the amplitude modulation stage, managed by a 2N2905 PNP transistor, which impresses audio information onto the carrier. Selective components (C3, C4, C7, C5) enhance voice frequencies within a +/- 5 kHz bandwidth, and modulation depth is controlled by R2 and R3. The project includes a 3-element L-type narrow bandpass filter (Ct3, L3, C10) to suppress harmonics and ensure a clean output signal. The project provides a complete schematic diagram, a comprehensive parts list including specific capacitor, resistor, and inductor values, and construction notes for the coils (L1, L2, L3). It also offers practical advice on enclosure requirements, suggesting an all-metal case or a PVC box with graphite paint for RF shielding. Operational parameters such as current draw (27mA@9V to 45mA@16V) and input impedance (50 Ohms) are specified, alongside guidance on antenna matching and the importance of a valid amateur radio license for 10-meter band operation.

The antenna is a VHF side is a 2m moxon, tuned on 145.825 MHz. The driven element of the moxon couples to a driven element for a 5 element 70cms Yagi, tuned on 436.5 MHz.