Would this be the control box used with the system that used SCR-274-N receivers on the ka-boom side? Best regards, Michael, WH7HG ex-K3MXO, ex-KN3MXO, WPE3ARS, BL01xh ex-Mensa A&P PP BGI I am me. I’m the only one who’s qualified. http://www.nationalmssociety.org/chapters/NTH/index.aspx http://wh7hg.blogspot.com/ http://kludges-other-blog.blogspot.com Hiki Nô!