2N1843 semiconductor manufactured by Sylvania, listed as 2N1843 (circa 1979).

2N1842A semiconductor manufactured by Sylvania, listed as 2N1842A (circa 1979).

2N1842 semiconductor manufactured by Sylvania, listed as 2N1842 (circa 1979).

2N1840 semiconductor manufactured by Sylvania, listed as 2N1840 (circa 1979).

2N1839 semiconductor manufactured by Sylvania, listed as 2N1839 (circa 1979).

2N1838 semiconductor manufactured by Sylvania, listed as 2N1838 (circa 1979).

2N1808 semiconductor manufactured by Sylvania, listed as 2N1808 (circa 1979).

2N1790 semiconductor manufactured by Sylvania, listed as 2N1790 (circa 1979).

2N1789 semiconductor manufactured by Sylvania, listed as 2N1789 (circa 1979).

2N1788 semiconductor manufactured by Sylvania, listed as 2N1788 (circa 1979).

2N1787 semiconductor manufactured by Sylvania, listed as 2N1787 (circa 1979).

2N1786 semiconductor manufactured by Sylvania, listed as 2N1786 (circa 1979).

2N1785 semiconductor manufactured by Sylvania, listed as 2N1785 (circa 1979).

2N1784 semiconductor manufactured by Sylvania, listed as 2N1784 (circa 1979).

2N1783 semiconductor manufactured by Sylvania, listed as 2N1783 (circa 1979).

2N1782 semiconductor manufactured by Sylvania, listed as 2N1782 (circa 1979).

2N1781 semiconductor manufactured by Sylvania, listed as 2N1781 (circa 1979).

2N1780 semiconductor manufactured by Sylvania, listed as 2N1780 (circa 1979).

2N1779 semiconductor manufactured by Sylvania, listed as 2N1779 (circa 1979).

2N1778A semiconductor manufactured by Sylvania, listed as 2N1778A (circa 1979).