1.

Transistor part numbers come and go. One of the problems that technicians often must solve is finding good substitute parts. Find some substitution guides and learn how to use them. Talk to other students, practicing technicians, and your instructor and ask them how they find replacement parts. Try to find out when substitutes work well and when they can be a problem. Can you find any Websites for substitutes? (There are many sites. One such example:)

http://www.nteinc.com/semiconductors.php?a=12

2.

Visit http://www.globalspec.com/electronics

It is a window to electronic components such as BJTs, FETs, diodes, and optoelectronic devices. By searching and browsing, you will find many interesting facts. As an example, there is an NPN transistor with the part number BUS50 that has a current rating of 70 amperes (or, try entering bus50 into your favorite search engine).. Browse this site and collect part numbers and characteristics for at least 6 devices. Share what you find with your instructor and classmates.