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A very quick and easy way to get on the air is to build a "Michigan Mighty Mite" CW transmitter for 160, 80, 40 or 30 meters. It can't get simpler than this. It has very few parts, costs almost nothing, and it works! Cost estimate $10 by VE6WTF

CW transceiver kits, QRP, frequency counters, QRP wattmeters, Dummy loads and QRP Parts

Small parts and kits for the QRPer

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.

Supplying Toroids, Electronic Parts and Kits to Engineers, Schools and Hobbyists. Capacitos, filters, inductors, qrp products

The direct conversion receiver described consists of only a bandpass filter, mixer IC, VFO and audio filter. With only 22 parts, this simple circuit should take a few hours at the weekend to construct.

An 80m transceiver using just 14 parts plus crystal and earpiece

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.

Online NOS electronic parts shop for QRP-QRPp radio constructors, to vintage radio and electrical measuring equipment restaurators. Many Germanium diodes, transistors and RF parts, semiconductors.

A home made Antenna Tuner made with a simple inductor and a few spare parts. Despite the title, the author succesfully tested this ATU with higher power inputs.

This is an uncommon loop antenna, hombrewed without the small feeding loop. With small spare parts is possible to build a loop antenna tuner for portable usage tha can ben used with common HF QRP transceivers

Paul McMahon presents a compact VSWR meter designed for QRP portable use, ideal for SOTA operations with rigs like the FT817. The device, constructed from readily available components, employs a simple resistive bridge for wideband performance from 1.8MHz to 52MHz, with diminishing accuracy at higher frequencies. Key features include no need for external power, simple calibration, and operation with low power levels. The design, detailed with parts lists, schematics, and construction guidelines, ensures a 2:1 worst-case VSWR to protect transceivers during antenna matching. Calibration points are set for accurate VSWR readings at various loads.

This page provides a detailed guide on building a 25 Watt QRP dummy load for hams. It includes a list of required parts and supplies, along with a documentation section. The project is aimed at hams interested in QRP operations and looking to build their own dummy load. The page offers step-by-step instructions and resources to help hams successfully complete the project.

This post discusses the Norcal 2N2/XX CW transceiver kit and provides suggestions for minor mods and parts substitutions. The author shares their experience assembling the kit and highlights the simplicity and joy of operating a QRP CW transceiver. The post also includes images and a list of recommended modifications towards the end. If you own or are interested in acquiring a Norcal 2N2/XX kit, this post offers valuable insights and recommendations to enhance your experience as a ham radio operator.