2N1506A semiconductor manufactured by Sylvania, listed as 2N1506A (circa 1979).

2N1506 semiconductor manufactured by Sylvania, listed as 2N1506 (circa 1979).

2N1505 semiconductor manufactured by Sylvania, listed as 2N1505 (circa 1979).

2N1502 semiconductor manufactured by Sylvania, listed as 2N1502 (circa 1979).

2N1500 semiconductor manufactured by Sylvania, listed as 2N1500 (circa 1979).

2N1499B semiconductor manufactured by Sylvania, listed as 2N1499B (circa 1979).

2N1499A semiconductor manufactured by Sylvania, listed as 2N1499A (circa 1979).

2N1499 semiconductor manufactured by Sylvania, listed as 2N1499 (circa 1979).

2N1495 semiconductor manufactured by Sylvania, listed as 2N1495 (circa 1979).

2N1493 semiconductor manufactured by Sylvania, listed as 2N1493 (circa 1979).

2N1492 semiconductor manufactured by Sylvania, listed as 2N1492 (circa 1979).

2N1491 semiconductor manufactured by Sylvania, listed as 2N1491 (circa 1979).

2N1490 semiconductor manufactured by Sylvania, listed as 2N1490 (circa 1979).

2N1489 semiconductor manufactured by Sylvania, listed as 2N1489 (circa 1979).

2N1488 semiconductor manufactured by Sylvania, listed as 2N1488 (circa 1979).

2N1487 semiconductor manufactured by Sylvania, listed as 2N1487 (circa 1979).

2N1482 semiconductor manufactured by Sylvania, listed as 2N1482 (circa 1979).

2N1481 semiconductor manufactured by Sylvania, listed as 2N1481 (circa 1979).

2N1480 semiconductor manufactured by Sylvania, listed as 2N1480 (circa 1979).

2N1479 semiconductor manufactured by Sylvania, listed as 2N1479 (circa 1979).