GenLog`s Burst CW Burst CW, as I call it, was incorporated in my CW keyer back in the 80`s and users liked the concept. So I added it to an early version of GenLog. Multi-speed CW messaging can be heard in many contests. Burst CW is when portions of a CW message are sent at increased speed, >30 wpm. During HF contests, the repetitive components of a message can be sent at very high speeds. 5NN, CQ, TEST, BK etc.