Bredhurst Receiving and Transmitting Society |
|
||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||
Close page to return MEASURING GAINS OF TRANSISTORS
The results obtained in the table are achieved because the two base resistors maintain a current flow of 5 micro amps. To carry out the same tests with PNP transistors use the same circuit but just reverse the supply connections. (A PNP transistor has to be biased on from the negative rail). RULES FOR SUBSTITUTION a transistor in a circuit. 1. The substitute transistor must be of the same variety (ie.silicon, NPN, switching as opposed to amplifying etc). 2. The substitute transistor should have about the same hfe value. 3. The substitute transistor should have the same or better ratings of maximum voltage and current. 4. The substitute transistor must physically fit - same case style and pinout and size :-)
|
|||||||||||||||||||||||||||
|
|||||||||||||||||||||||||||
|