Many special event stations will be active around the world this week to celebrate the 50th anniversary of the first human space flight Special event stations R50YG and R50SK are active from Baikonur until April 14 and the special call R50KEDR will be on the air on April 12 from 0507 to 0655z to commemorate the 108 minutes of Gagarin’s first flight.
Ari OH3KAV has posted this list of Russian stations that will be active:
R50YG “Yuri Gagarin”
R50SK “Sergey Korolev”
RG50F Star City training center
RG50C Landing Site
R3K Energya Space Flight Control Center Clint Bradford K6LCS has posted this collection of Yuri Gagarin links