> > > On Wed, Jan 11, 2012 at 11:13 PM, G. E. Janssens - K5WW <k5ww at live.com> wrote: > > > It appears to be different for every caller, varies is lenght and tone. > Which makes me think it's some kind of "digital" ID. > > Could it be RSID? http://www.w1hkj.com/RSID_description.html If so, somebody forgot to turn it off before the contest. 73, Doug K4DSP