Classroom Practice Oscillator This is a good quality CW practice oscillator .It uses a different chip and circuit than the orginial SPO-1. This offers a smoother / louder control of the volume, a better tone quality and more stable frequency over the full volume range. A great choice for anyone undertaking a construction project as part of a Ham Radio training course. The kit is complete with a 50mm loudspeaker, all parts and high Quality PCB.
Classroom Practice Oscillator SPO-2
Full Kit Instructions can be downloaded here (Use these to make your own if you wish
Kit with all board mounted parts, Volume control and speaker