Can anyone recognise these transistors and recommend a replacement?

[ThaFresh]

Hi my V-Net 4150 car amp stopped working recently, I suspect it was the decks fault as its been playing up. I took the cover off and found these 8 transistors burnt out. Some of the markings have been burnt off and I cant find any information on them or possible replacements based on the exisiting markings.

Does anyone here have any idea what they are and what I could replace them with?

heres a pic
http://www.vanillainteractive.com/amp.jpg

its 250k and a big pic so you can see the markings easily

Thanks

[Stuart Easson]

They are probably 50n06 FETs (n-channel, 50amp, 60v). Onsemi makes a handful of different useable replacements. I've used mtp75n05hd's in car amp repairs very successfully.

Were these in the audio amps or the power supply?

Since the power supply only turns them on and off, an exact match is less critical, you just need to make sure you have at least the same current and voltage rating. It might be helpful to make sure they all come from the same batch, then you will know they have approx. the same performance.

Good luck...

Stuart

[Duo]

That is one of the very best car amp blow outs I've seen. Very artistic how it went.

They look like they would probably be use in the power supply. Better check the output transistors to see if they went as well.

[jackinnj]

those are Fairchild www.fairchildsemi.com devices -- just plug the p/n into their search engine.

[EWorkshop1708]

Holy ****, I've NEVER seen 8 MOSFETS go up in smoke like that before!

Maybe next time, use a lower rated fuse, so if the amp ever blows again, you don't nearly catch the thing on fire

EDIT: Like said before, go to onsemi.com to get transistors, and order a bunch, so you have some for future use.

[Duo]

Hehe, at a place where I worked, we had a few amps come in from kids where every single power semiconductor in the unit was blown like that. To our unamazement, the owners stated rediculous supply and load conditions imposed upon the amplifiers, which were junk amplifiers in the first place.

[EWorkshop1708]

Originally posted by Duo
Hehe, at a place where I worked, we had a few amps come in from kids where every single power semiconductor in the unit was blown like that. To our unamazement, the owners stated rediculous supply and load conditions imposed upon the amplifiers, which were junk amplifiers in the first place.

Agree.

The biggest cause of failure I've seen from amps I've worked on, is because someone will take a cheap 2 channel amp rated 2ohms/ch stereo 4ohm bridged and parallel the wiring from 2 subwoofers in a standard dual box (making 2 ohms) and running the amp bridged to get "more power"