Orion 2250SX

[blazer40]

I'm hoping someone might have nudies of an Orion 2250SX here? I just got a real basket case: this amp has no outputs or power supply transistors attached! From some searching it looks like outputs on this are 2n6488/6491's, correct? I have no clue what the power supply uses though, need some help here. There also appears to be a missing optocoupler mid board, are both of them the same part number?

TIA!
-Blazer40

[Perry Babin]

The original PS FETs in some of the 2250s were SMP50N06s.

The optocouplers are the same.

[blazer40]

Thanks for that! I've also found (from various pictures I have found) that there are some 317/337 regulators on the one side of the board by the outputs, is there anything mixed in with the 50n06's on the power supply side of the board? My problem is lack of good photos of the ps section at this point..

TIA,
Blazer40

[Perry Babin]

The following are all I have on that amp. If there's something that you can't see, I have some of the 2100 which is similar and I'll upload the ones you need or tell you what the parts are.
http://www.bcae1.com/temp/orion2250sx.zip

[iamsonic]

I am working on a 2250SX also.

It seems they mixed the 2n6488 transistors with the 2n6491 transistors. The quantities of them in this amplifier make no sense. One side has five 2n6491 and seven 2n6488. the other side {yellow side} has eleven 2n6488 and one 6491.

the 2n6491 is PNP (as far as I know) and the 2n6488 is NPN.. so they shouldn't be interchangeable.
http://www.onsemi.com/pub_link/Collateral/2N6487-D.PDF

the workmanship was decent and the amplifier didn't show signs of repair but I'm believe it was repaired and the repair person didn't get the correct parts.

Because there are more 2n6488 transistors , I'm guessing the 2n6491 NPN are the transistors put in place of the originals.

Perry, I know your name and I thank you for your contribution to the car audio communities!

[iamsonic]

from what I've gathered, the first five of each output are 2n6491 the second five are 2n6488, the 317t and 337t

here is what I have so far. I will try to finish at least the parts which commonly fail. This is my first time working with a 2250sx. I see why the output is the common failure point. The power supply is stout and can take abuse. the outputs are weak compared to amplifiers like a Lanzar 2500.

[iamsonic]

edit, based on the images Perry has in the zip file, the power supply is half and half also. the first half is SMP50n06. the Second half is SMP60n06

[Perry Babin]

All of the power supply FETs were SMP60N06s. The others were replacements.

[blazer40]

Nice pic iamsonic!!! So you have a pretty butchered up amp too? I am thinking of running all rfp50n06's in the ps section on the one I have. There are sooo many parts pulled on the amp I have it's nuts.. I am just going to take things slowly and go section by section, starting with the PS first. This definitely is/has been a treasure hunt so far!

[iamsonic]

Originally Posted by Perry Babin

All of the power supply FETs were SMP60N06s. The others were replacements.

[got it]
What about the outputs? did I get them right?
The amplifier I am working on has radial capcitors {stand up caps} I assume the transistors don't change for that version?
Is there any way the amplifier I started on today worked between when the last guy threw the parts in and now?
(there are 2n6488 and 2n6491 transistors where the 317t and 337t go. and the rest are in there willy-nilly.)

Originally Posted by blazer40

Nice pic iamsonic!!! So you have a pretty butchered up amp too? I am thinking of running all rfp50n06's in the ps section on the one I have. There are sooo many parts pulled on the amp I have it's nuts.. I am just going to take things slowly and go section by section, starting with the PS first. This definitely is/has been a treasure hunt so far!

Thanks, I figure it will help {if I get it right}
the power supply in the amp I'm working on seems good so I'm happy there and the caps are all very nice. Getting the output sorted out is the hard part. Before pulling the rails and finding out the transistor mix up I found one output transistor which was reading a short across the outside legs and I thought.. man it can't be this easy...
well, it's not that easy..
I'm not bothered much by it all but I wish whoever touched it had never gotten their hands on it.[even though they did a nice clean job screwing it up]