The 1970s newsletters are here. There are index files that may help you find specific topics.
1970-01.pdf
1970-02.pdf
1970-03.pdf
1970-04.pdf
1970-05.pdf
1970-06_Index.pdf
1970-10.pdf
1970-11.pdf
1970-12.pdf
1971-01.pdf
1971-02.pdf
1971-03.pdf
1971-04.pdf
1971-05.pdf
1971-10.pdf
1971-11.pdf
1971-12.pdf
1972-01.pdf
1972-02.pdf
1972-03.pdf
1972-04.pdf
1972-05.pdf
1972-10.pdf
1972-11.pdf
1972-12.pdf
1973-01.pdf
1973-02.pdf
1973-03.pdf
1973-04.pdf
1973-05.pdf
1973-10.pdf
1973-11.pdf
1973-12.pdf
1974-01.pdf
1974-02.pdf
1974-03.pdf
1974-04.pdf
1974-05.pdf
1974-10.pdf
1974-11.pdf
1974-12.pdf
1975-01.pdf
1975-02.pdf
1975-03.pdf
1975-04.pdf
1975-05.pdf
1975-10.pdf
1975-11.pdf
1975-12.pdf
1976-01.pdf
1976-02.pdf
1976-03.pdf
1976-04.pdf
1976-05_Index.pdf
1976-10.pdf
1976-11.pdf
1976-12.pdf
1977-01.pdf
1977-02.pdf
1977-03.pdf
1977-04.pdf
1977-05.pdf
1977-10.pdf
1977-11.pdf
1977-12.pdf
1978-01.pdf
1978-02.pdf
1978-03.pdf
1978-04.pdf
1978-05.pdf
1978-10.pdf
1978-11.pdf
1978-12.pdf
1979-01.pdf
1979-02.pdf
1979-03.pdf
1979-04.pdf
1979-05.pdf
1979-10.pdf
1979-11.pdf
1979-12.pdf