John, The preamp is from QST, August 1988, pages 22-24 titled "Preamplifier for 80- and 160-M Loop and Beverage Antennas" Took a while to find it. Could remember seeing it in my reprint file but not where. My QST collection was given away when I moved last year and haven't gotten around to getting the digital collection. 73 Don K5AQ