I have no idea what I bought it for so many years ago but it is new/never used. I must have seen a mod in QST for one of early 70's pieces of Heathkit ham gear. Cannot find it listed in the only available parts x-ref for Heathkit gear. Anyone who wants it give me your address and I will mail it. 73, Dick KF4NS St. Petersburg, FL 33714 USA Keep the glow!