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Makers of the Xforce Amplifier

HamCalc is a free collection of calculators for radio amateurs include Antenna ERP calculations, Attenuators, Audio Filter design, Coil Winding, Decibels, Great Circles map and calculator, HF Filters, HF Traps, Metric conversions OP Amps QRA Locator to Latitude/Longitude, Radio Horizon calculator, Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations Download zip By G4VWL

The website https://www.qsl.net/dl5dbm showcases homebrew projects related to KW, 2-meter, 6-meter, antennas, amplifiers, preamps, power supplies, and more. It provides information and resources for radio amateurs interested in DIY projects and experimentation.

Two types of home-brewed 12/20 Ampere 13,8volt power supplies, including detailed part lists by ON6MU

Founded in 1992 this DXing club has over 1725 members and is based on the 6288 feet high summit of Mount Washington in Sargents Purchase, New Hampshire, USA

Name Badges, Plastic Signs Desk Stands License Plates & Frames Rubber Stamps, and QSLs

Source of common model manuals and amateur help on amplifier problems for the amateur bands, Discussion of vacuum tube amplifiers. Technical information and discussion of obselete tube replacement.

Repeaters, transmitters, receivers, small power Amps and Controllers

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

20/22 Ampere or 30/32 Ampere 13.8 volts power supply RE-PSF14A20 or PSF14A30 by ON6MU

If the display lamps in your TS-2000 go out. They can be replaced with LEDs.

How to get the most from attenuators and preamps

Produce QSL & post cards, stickers, ID cards, calendars, certificates, awards, membership applications, log and call-books, rubber stamps,T-shirts, brochures, advertising materials.

About dummy loads, what are they and how to build one

HF and VHF amplifiers homebrewed by GM3WOJ

BIRD RF power measuring, new and used, HENRY RF power amplifiers (used HF amps), TOHTSU coaxial relays, SAMLEX power supplies, RFI chokes reduce interference, Parts parts, tubes, Used amplifiers, radios, antennas and accessories, Los Angeles, CA.

Portable Base Systems, Mast Clamps, Aluminum Tubing

The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.

Two types of multi-functional Home-brew 6/8Amps - 20 Ampere variable power supplies by ON6MU

Ameritron Al-811H Tuning for Power/Dissipation/Linearity, and More Generally 811A Tube Amps in Grounded Grid

This article presents a method of controlling preamps, antenna switching and polarization switching remotely without the use of control cables.

Design guidelines for Op Amp audio preamplifier circuits by Mike Martell N1HFX

How the tube converts DC to RF Power

Authorized ham radio store for Alinco Vibroplex Pryme MFJ Enterprises Mirage Amps Ameritron Vectronics DCI Yaesu Comet Antenna

Hidden transmitter hunting, often called fox hunting or Amateur Radio Direction Finding (_ARDF_), presents a unique challenge for radio amateurs. This resource details the _PicCon_ controller, a specialized device designed to automate the transmission of signals for such events. It integrates with a standard radio transceiver, functioning similarly to a packet radio TNC, by controlling the Push-To-Talk (PTT) line and injecting audio tones or modulated CW Morse code into the microphone input. The _PicCon_ unit is field-programmable using DTMF tones received via the radio, storing all settings in EEPROM for power-off retention. Its compact design and low power consumption (a few milliamps from a 7-35VDC source) make it suitable for remote deployment. An onboard LED indicates operational status, and a push-button allows manual start/stop of transmissions without DTMF. Typically supplied as a kit, _PicCon_ includes a PCB, components, and a comprehensive manual (available in HTML, RTF, and PDF formats). The kit provides a six-conductor interface cable, but users must supply radio and power plugs due to varied configurations. Byon, _N6BG_, developed this controller, which is available from the Byonics website.

Resource for finding data on vacuum tubes.

What become our QSL once sent ? QSL routes, IRC and green stamps, the best and worst practices.

Pre-inked - re-inkable stamps

In this PDF article Zack Lau describe how to homebrew a four element yagi beam antenna for 50 MHz band, including how to build mounting blocks and tubing clamps to hold elements.

This is an internet resource for those interested in guitar amplifiers, vacuum tubes, and design tools such as SPICE modelling.

Radio Frequency Interference To/From touch lamps and dimmers

Amplifier repair and conversion, specialize in converting HF amplifiers to operate as monoband amps on 50 MHz

This test circuit is easy to duplicate, and demonstrates the extreme voltages that appear in an amplifier when the load is improper for the amount of drive power applied.

Who needs a GaAsFET? Tuning, constructions and Packaging by Paul Wade

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

Techni-Tool is a distributor of electronic production tools, oscilloscopes, multimeters, power supplies, cases, tool kits, cutters, wrenches, crimpers, solder desolder stations, BGA, microscopes, lamps, static control, workstations, chairs, torque screwdrivers, tweezers, dusters, chemicals.

1.2 to 30 Volts 1.5 Amps Power Supply

ARRL special service club

Southeast New Hampshire W1SRA / 147.000Mhz / Negative Offset / 100.0 PL Tone Welcome to the Sunday Night Net each Sunday evening at 8:00 PM.

A lot of good things, not for QRP fans.

Information about RF driven lamps

715 days, 6 hours, 58 minutes, and 29 seconds of uptime are reported for the YSFReflector-Dashboard by DG9VH, which monitors the IT C4FM SUD / ITALY-SUD reflector. This dashboard, compiled on December 1, 2017, provides real-time operational statistics for the reflector, including system information, disk usage, and connected YSFGateways. The dashboard also features a "Last Heard List" and an "All Heard List," displaying callsigns, durations, and timestamps (Europe/Rome) of stations active on the reflector. These lists offer a quick overview of recent activity, which can be useful for tracking **C4FM** traffic. While the resource is titled "IZ7AUH-6 DX Web Cluster," the primary content displayed is a **YSFReflector** dashboard. This suggests the platform might serve a dual purpose, offering both traditional DX cluster services and monitoring for Yaesu System Fusion reflectors.

QSL Printer shop, products include Photo QSL cards, Eyeball cards, and State QSL Cards, based in Hampstead, MD USA

Common causes of failues, due to wrong clamps. About Guy Anchors

Linear amplifiers cold adjustments with network analyser (VNA)

Technical specifications and details of the Yaesu FL-2100B HF Power Amplifier

Printing QSL cards, postcards, advertising materials, bussines cards, calendars, stickers, t-shirts, gold printed advertisements, rubberstamps, and QSL lables from Bulgaria. See also LZ QSL Printing Service web site

Maxdao: offer you 7/16, N coaxial connectors, jumper cables, feeder clamps and grouding kits, surge arresters & brackets, wall entries and microwave components used in base tower, power dividers, couplers

Tips and advice compiled from The DX Reflector

The WB5RVZ Genesis Radio G40 build log documents the construction of a 5W QRP 40m SDR transceiver kit, detailing each phase of assembly from power supply to RF filtering. It provides specific component lists, parts placement diagrams, and testing procedures for stages like the local oscillator, Tayloe detector, and RX op-amps. The resource highlights discrepancies between documentation versions and offers practical advice for builders, including a "virtual build" approach to preemptively address potential ambiguities in component identification and placement. It also addresses a specific "VK6IC Fix" for early board revisions, involving trace cuts and jumper wires for improved performance. The build log presents measured voltages and expected current consumption for various stages, such as the 4.9-5.0 Vdc on the 5V rail and under 100mA for RX current. It outlines critical adjustments like image rejection tuning, a common procedure for direct conversion receivers. The resource also includes practical tips for handling components like the 2N3866 transistor and its heatsink, emphasizing pre-assembly. It details the winding of two 1.45 uH toroidal inductors on T50-6 cores with 17 turns of #20 AWG wire, crucial for the RF path.