TIP 42 test cct.

With no resistor to limit the collector current, this transistor could draw as much as 2.8 amps, dissipating 25 watts until it burns up unless you have a big heat sink on it.
 
Heres what I usually see, I thought the lamp symbol you used was a meter also.
 

Attachments

  • lamp.jpg
    2 KB · Views: 566
thx alot for the test circuit. Well, the tip42 appears to be working fine in the test circuit, i actually get a voltage reading coming fromt he collector. But, when i put it into my board for this schematic (see below), i get .3v where there should supposedly be some voltage more or less 8-9v i guess. Am i wrong or...

**broken link removed**
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…