Band Pass Filter kit set

This item is a set of 10 band pass filters (BPF), one for each of the HF bands 160, 80, 60, 40, 30, 20, 17, 15, 12 and 10m. The filters are designed for receiver input filtering and use the popular double-tuned-circuit which is reliable and easy to build, without needing access to any special equipment. The kits…

QCX+ 5W QRP CW HF transceiver

The “QCX+” (QRP Labs Xcvr +): a feature-packed, high performance, single band 5W CW transceiver kit with WSPR beacon and built-in alignment and test equipment. Available for 80, 60, 40, 30, 20 or 17m bands. Experimental use on 15, 12, 10 or 6m (lower power output and reduced sensitivity). For complete details see http://qrp-labs.com/qcxp The Optional enclosure is black anodized…

QDX – Digital QRPp Transceiver

The “QDX” (QRP Labs Digital Xcvr): a feature-packed, high performance, four-band (80, 40, 30, 20m) 5W Digi-modes transceiver kit, including embedded SDR receiver, 24-bit 48 ksps USB sound card, CAT control, synthesized VFO with TCXO reference. QDX transmits a SINGLE SIGNAL, it is not an SSB modulator with associated unwanted sideband and residual carrier, or intermodulation due to amplifier…

SDT21 simple digital QRPp transceiver

simple “digital” monoband transceiver SDT21 The goal of this project was the development of a simple to build CW monoband transceiver based on the direct superheterodyne principle with crystal control a la “PIXIE” or “Rockmite”, but with much better technical data. To minimize the circuit effort, the concept should be as highly integrated as possible…

"OM4001A" HF Linear Amplifier

General description and the advantages of the OM4001A amplifier. (Also read : https://www.cqdx.ru/ham/qro-qrp/om4001a-hf-linear-amplifier/) The OM Power model OM4001A is an automatic power amplifier, designed for use on all short wave amateur bands from 1.8 to 29.7 MHz (including WARC bands) and all modes. It is equipped with a two pieces of ceramic tetrode FU728F. The…