2N2143 semiconductor manufactured by Sylvania, listed as 2N2143 (circa 1979).

2N2142A semiconductor manufactured by Sylvania, listed as 2N2142A (circa 1979).

2N2142 semiconductor manufactured by Sylvania, listed as 2N2142 (circa 1979).

2N2141A semiconductor manufactured by Sylvania, listed as 2N2141A (circa 1979).

2N2141 semiconductor manufactured by Sylvania, listed as 2N2141 (circa 1979).

2N2140A semiconductor manufactured by Sylvania, listed as 2N2140A (circa 1979).

2N2140 semiconductor manufactured by Sylvania, listed as 2N2140 (circa 1979).

2N2139A semiconductor manufactured by Sylvania, listed as 2N2139A (circa 1979).

2N2139 semiconductor manufactured by Sylvania, listed as 2N2139 (circa 1979).

2N2138A semiconductor manufactured by Sylvania, listed as 2N2138A (circa 1979).

2N2138 semiconductor manufactured by Sylvania, listed as 2N2138 (circa 1979).

2N2137A semiconductor manufactured by Sylvania, listed as 2N2137A (circa 1979).

2N2121 semiconductor manufactured by Sylvania, listed as 2N2121 (circa 1979).

2N2108 semiconductor manufactured by Sylvania, listed as 2N2108 (circa 1979).

2N2107 semiconductor manufactured by Sylvania, listed as 2N2107 (circa 1979).

2N2106 semiconductor manufactured by Sylvania, listed as 2N2106 (circa 1979).

2N2105 semiconductor manufactured by Sylvania, listed as 2N2105 (circa 1979).

2N2104 semiconductor manufactured by Sylvania, listed as 2N2104 (circa 1979).

2N2102S semiconductor manufactured by Sylvania, listed as 2N2102S (circa 1979).

2N2102L semiconductor manufactured by Sylvania, listed as 2N2102L (circa 1979).