1N5581A semiconductor manufactured by Sylvania, listed as 1N5581A (circa 1979).

1N5531B semiconductor manufactured by Sylvania, listed as 1N5531B (circa 1979).

1N5381 semiconductor manufactured by Sylvania, listed as 1N5381 (circa 1979).

1N5342 semiconductor manufactured by Sylvania, listed as 1N5342 (circa 1979).

1N5254B semiconductor manufactured by Sylvania, listed as 1N5254B (circa 1979).

1N5199 semiconductor manufactured by Sylvania, listed as 1N5199 (circa 1979).

1N5749 semiconductor manufactured by Sylvania, listed as 1N5749 (circa 1979).

1N5581 semiconductor manufactured by Sylvania, listed as 1N5581 (circa 1979).

1N5531A semiconductor manufactured by Sylvania, listed as 1N5531A (circa 1979).

1N5380B semiconductor manufactured by Sylvania, listed as 1N5380B (circa 1979).

1N5341B semiconductor manufactured by Sylvania, listed as 1N5341B (circa 1979).

1N5254A semiconductor manufactured by Sylvania, listed as 1N5254A (circa 1979).

1N5198 semiconductor manufactured by Sylvania, listed as 1N5198 (circa 1979).

1N5748B semiconductor manufactured by Sylvania, listed as 1N5748B (circa 1979).

1N5580B semiconductor manufactured by Sylvania, listed as 1N5580B (circa 1979).

1N5530B semiconductor manufactured by Sylvania, listed as 1N5530B (circa 1979).

1N5380A semiconductor manufactured by Sylvania, listed as 1N5380A (circa 1979).

1N5341A semiconductor manufactured by Sylvania, listed as 1N5341A (circa 1979).

1N5254 semiconductor manufactured by Sylvania, listed as 1N5254 (circa 1979).

1N5197 semiconductor manufactured by Sylvania, listed as 1N5197 (circa 1979).