This Cinderella stamp is from 1925. KDKA radio in Pittsburgh went on the air in 1920 and WBZ in Boston came on soon after in 1921 – they did a remote broadcast from this expo. Surprisingly, there were many radio stations on the air in ’25, enough to spur a lot of interest in receivers and tubes…and batteries. As former DXer, I know the excitement of pulling in some exotic, far away station that faded in and out as the ionospheric waves bounced the signal. The much later, much lauded Sony ICF 2010 receiver has circuitry to stabilize these signals. One up on the old Hallicrafters…
This Cinderella is 1.875 x 2.375″ on flimsy paper. The orange-y ink bleeds through to the reverse.
Uncle Bob's Pix 