Il 2013-01-22 23:19 Tom Van Baak (lab) ha scritto: > Yes, Don, those old quartz bars are rare and amazing: > > http://leapsecond.com/museum/gr676b-50kc/ > http://leapsecond.com/museum/gr1190a/ What is the function of the (metal?) disc plates near the two ends of the rods? Their position seem to be trimmable. Thank, Fabio.