Help with Orion 2150 Gx

[v-dub-guy]

I bought this Amp at a Police auction and I hooked the positive and the ground and the remote turn on , When i turn on my Cd player I get a high pitched sound and then it blows my inline 40 Amp fuse. Any help would be greatly appreciated.

[I Am An Idiot]

Sounds like you have some shorted output transistors. Do you have an Ohm meter?

[v-dub-guy]

Yes i just bought one. When I opened the amp up i didnt see any damage or anything burnt if that helps

[spooney]

dude i have one of these as well.I get the same high pitched squeal when i power it up but without the blown fuse. I'd definitely ohm out the output transistors and check for shorts.Also check the mpsu07's and mpsu57's in the preamp section. I had somebody on here tell me that the high pitched squeal was because of failing or out of tolerance rail caps(the large ones in the center of the amp).I've yet to replace mine so I can't say for sure if that is a guaranteed fix for the squeal but based on who I got the info from I would think it would help.

[spooney]

Theres tons of info in this thread about your amp: Old School Orion 2150 gx.I must repair this amp

[v-dub-guy]

I agree there is a ton information but if you dont understand the terms they use then you're stuck. What should the ohms read across the four big blue things? The sound seems to be coming from the big circle thing thats wrapped in wires.

[spooney]

does it look like the insulation on the big blue caps has shrunk?By that i mean has the sleeve on the outside of the cap came off from around the ends of the cap and started moving towards the middle of it. If they look anything like mine in this pic they are probably shot . Check it out here: http://www.putfile.com/pic.php?img=4367970

I wouldn't worry about measuring the resistance on the caps.You should check the 16 transistors mounted to the heatsink on the end near the rca/DIN jacks. If you get any readings near 0 ohms between any of the three legs the transistor is bad.They are in 4 groups of 4 . If any one in a group is bad you should change all 4 in that group at least and preferably all transistors in that channel.

[I Am An Idiot]

Set the meter to the diode test function. The output transistors will (as stated earlier) be on the end of the amp near the RCA jacks. They will each have a 2 watt resistor connected to it. These will be the larger resistors on the board and there will be 8 on each side of the amp. Place one meter lead on the middle leg of one of the transistors. Place the other lead on the left leg of the same transistor. Notice the reading on the meter. Remove the lead from the left leg and place it on the right leg, again notice the reading of the meter. As stated earlier it will appear that you have 4 or 8 shorted transistors. Let us know what you come up with.