OHR 100A single band CW transceiver kit

The Oak Hills Research OHR 100A single band CW transceiver kit is offered in 80, 40, 30, 20, and 15 Meter versions. Each can be aligned to cover 70-80Khz in a fairly wide band, but here are the defaults for which detailed specification is provided in the manual: 15M 21.000 – 21.070 20M 14.000 –…

Four Tube Superheterodyne Radio Kit

Build your very own superheterodyne radio. Simple to follow instructions with schematics and wiring diagrams! You get a manual, all the parts including silk screened printed circuit board, 4 tubes, sockets, tuning capacitor, Aerial, Oscillator and IF coils, 4 inch speaker, resistors, capacitors, wire, nuts and bolts etc. Four Tube Superheterodyne Radio Kit (Limited Edition)…

Building the “Toothpick” Audio CW Filter

“Toothpick” Audio CW Filter Kit Variable bandpass helps peak desired signal Audio amplifier will drive speaker to room filling volume In / out switch Use with phones or speaker Will work with other qrp rigs and older receivers Measured peak bandpass 700 to 1000 Hertz Introduction: The “toothpick” is a simple variable bandpass audio filter…