The MKB-300 came out in 1985 , it's the 76 key version of the MKB-1000 . It's part of ROLAND's first MIDI line up along with the JX-3P , JX-8P , JUPITER-6 , JUNO-106 , TR-909, MKS-80 , MKS-70 , and MKS-10 and MKS-30 .