These have more than likely been seen before, but just in case.
The credit goes to Nakahiro Tokeikan.
1970

http://nakahiro.parfait.ne.jp/cataro.../rado1970.html

1972

http://nakahiro.parfait.ne.jp/catarog/moji/rado1.html

http://nakahiro.parfait.ne.jp/catarog/moji/rado2.html

http://nakahiro.parfait.ne.jp/catarog/moji/rado3.html

http://nakahiro.parfait.ne.jp/catarog/moji/rado4.html

http://nakahiro.parfait.ne.jp/catarog/moji/rado5.html