Published:2009/7/11 2:28:00 Author:May | From:SeekIC
Skin resistance of about 10k creates dashes when finger touches grid pattern on left side of paddle and dots when other finger touches pattern on other side. Transistors act as solid-state switches. Developed for use with Heathkit CW keyer HD-10. Supply is 10V, obtained from 10-V zener connected through appropriate dropping resistor to higher-voltage source. Article covers construction of paddle by etching printed-wiring board.-T. Urbizu, Try a Sensor Keyer, 73 Magazine, Jan. 1978, p 184-185.
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