SP-X - A pocket QRP CW rig for 40 to 17m

A homebrew four band QRP CW rig designed for mountaineering (SOTA), parks (WWFF) and portable outings. Loosely modelled on the excellent Mountain Topper Radio rigs, but with a twist -- it is channelised (no tuning knob or display!) because portable CW such as SOTA or Parks is mostly on recognised calling frequencies. Includes a ’guided tour’ under the covers and video from two VK3 SOTA summits. A full description, including accurate schematics, is available at: