I need some help. My slayer exciter which previously worked all the sudden doesn’t, and I haven’t a clue as to why. I am using the most basic circuit for it. The primary is 1 turn and the secondary is 1200. Previously used TIP41C now using TIP31C

 

You are probably aware that many sudden failures are because of dying semiconductors. Yes, it is true capacitors seem to fail at a high rate also. There are not too many parts in you circuit, so maybe you can test them individually (usually with a DMM).

 

Did it stop working when you changed the transistor? That would be a clue!

 

Post your schematic. One turn may be too little.

 

Using this simple circuit, you’ve probably all seen it before.

 

I also believe that a single primary turn is incorrect. All instances of the slayer circuit indicates at least 3 or 4 primary turns.
Additionally, everyone mentions that this is a very temperamental circuit and it is difficult to make it work properly.