Hi Marv, I'm in for the HP8556A SA LF unit manual. How do we work that? 73 de Mike W5VSI Littleton, CO 80128 On 6/6/2011 11:57, Radio WC6W wrote: > 8556A Spectrum Analyzer LF unit -- $30 -- Mike Manes mrmanes at gmail.com Tel: 303-979-4899 "Things should be made as simple as possible, but not more so." A. Einstein