so this week i did my first build using trannies other than j201/etc
i noticed that when the metal case of the transistor touched the inside of the enclosure all hell broke loose. i wrapped the cans up with some electrical tape and everything was good.
i know it's dangerous to assume, but i would guess that the metal case of the transistors should be grounded by default? am i out to lunch?
Quote from: zilla on February 24, 2015, 04:55:11 PM
so this week i did my first build using trannies other than j201/etc
i noticed that when the metal case of the transistor touched the inside of the enclosure all hell broke loose. i wrapped the cans up with some electrical tape and everything was good.
i know it's dangerous to assume, but i would guess that the metal case of the transistors should be grounded by default? am i out to lunch?
Not all transistors have their housing grounded. Most of them in the TO-220 package have the metal part of the housing connected to one of the pins (often the middle one iirc). If none of the pins goes to ground, the housing can not be grounded. It's pretty stupid if you ask me, no idea why they are produced this way.
hope this helps
EDIT: just remembered that there are also TO-220 with the metal part of the housing unconnected to the pins. Seems to differ from part to part. Checking the datasheet seems vital once more
ok. this helps a lot.
thanks