Blowing Fuses in my Yamaha CA-600

[avionic]

The flat side does lie against the heatsink. Did I screw it up?

:yes: Its install 180 degrees out. Needs to be flipped around.

 

[TheDr]

I flipped it around and the resistors are still smoking.

Not to argue because I know you have VAST more knowledge about this but according to this datasheet the base should be on the left side with flat side facing away from me. The service manual shows the base the trace(?) closest to the corner. If that were the case wouldn't the flat side go against the heatsink? I'm confused where I messed it up. :tears:

 

[avionic]

I flipped it around and the resistors are still smoking.

Not to argue because I know you have VAST more knowledge about this but according to this datasheet the base should be on the left side with flat side facing away from me. The service manual shows the base the trace(?) closest to the corner. If that were the case wouldn't the flat side go against the heatsink? I'm confused where I messed it up. :tears:

That is correct(ksc1845) but.. the little outhouse shaped 2sc458 the sloped roof corresponds to the flat side of the KSC1845.

 

[TheDr]

Now I'm wondering what other transistors I screwed up. According to the Service Manual 2SD371 should be on the side opposite the fuses and 2SB531 should be on the side of the fuses correct?

 

[TheDr]

That is correct(ksc1845) but.. the little outhouse shaped 2sc458 the slopped roof corresponds to the rounded side of the KSC1845

The Service Manual image of the Main Amp board is actually a mirror of what the board looks like, not sure if that changes things.

 

[avionic]

The Service Manual image of the Main Amp board is actually a mirror of what the board looks like, not sure if that changes things.

Did the 2SC458 look exactly like the KSC1845?

 

[TheDr]

Did the 2SC458 look exactly like the KSC1845?

Kind of, it has one big flat side and then a smaller flat side. Is that what you mean?

Now that I compare the other boards they are all mirror images. I'm guessing that it's laid out as if I were look at the soldering side. Not sure if that's normal or not. Don't have much to compare it to.

 

[avionic]

Kind of, it has one big flat side and then a smaller flat side. Is that what you mean?

Its not kinda other than it had 3 pins. The smallest flat side is the back side and from the front side the pins are BCE.. The 1845 looking at the flat side is ECB. The largest flat side of the 458 was pressed against the heatsink.

 

[TheDr]

So comparing to this data sheet the round side is the larger flat side of my 2SC458?

 

[petehall347]

some pictures may well help if at all possible .
with components possibly in the wrong place its almost beyond my knowledge to help here .but i can compare pictures to try and work things out .

 

[avionic]

So comparing to this data sheet the round side is the larger flat side of my 2SC458?

Yes.There are two styles of 2SC458 .. The little "outhouse" TO-92 style and the regular TO-92 style

 

[TheDr]

Here is the removed transistor on the left and a replacement on the left. Let me know if you need different angles or a pic of anything else. Also a picture of the main amp board I have hooked up.

 

[avionic]

Look at this schematic.In the lower left hand corner shows a diagram of the 458 in question with pin identification.
Disreguard the typo on the diagram(2sa458) its suppost to be 2SC458
http://sportsbil.com/yamaha/c-4-s.pdf

 

[avionic]

I've only probably replace a couple hundred of these..

 

[TheDr]

So the transistor I have is actually a 2SA458?

Now I'm really confused.

Does that mean all my transistors are in backwards?

Believe me when I say I don't doubt you, I was just trying to learn from my mistakes, all of your help is more than appreciated. After all of your help I think I owe you a drink of your choice.

 

[avionic]

So the transistor I have is actually a 2SA458?

Now I'm really confused.

Does that mean all my transistors are in backwards?

Believe me when I say I don't doubt you, I was just trying to learn from my mistakes, all of your help is more than appreciated. After all of your help I think I owe you a drink of your choice.

No.Reread my edited post. It is a 2SC458. It is printed on the old transistor C458.....................

 

[TheDr]

I had previously swapped it around but I'm still getting smoke (since I swapped the board the old resistors smoke up faster). If you go by the pic I have posted I have the MJE182 installed on the left and the MJE253 installed on the right, both with silver square facing down. I also have the original 2SB om the left and the 2SD on the right.

Are these installed correctly?

 

[avionic]

I had previously swapped it around but I'm still getting smoke (since I swapped the board the old resistors smoke up faster). If you go by the pic I have posted I have the MJE182 installed on the left and the MJE253 installed on the right, both with silver square facing down. I also have the original 2SB om the left and the 2SD on the right.

Are these installed correctly?

I'll have to look it up later.My computer mouse is flaking out on me.Have to restart computer.

 

[avionic]

I had previously swapped it around but I'm still getting smoke (since I swapped the board the old resistors smoke up faster). If you go by the pic I have posted I have the MJE182 installed on the left and the MJE253 installed on the right, both with silver square facing down. I also have the original 2SB om the left and the 2SD on the right.

Are these installed correctly?

MJE182 and MJE253 looking at the metal side ECB
2SC1382 looking at the side with 3 impressions around the mounting hole ECB
can't find a data sheet for the C682

 

[TheDr]

Then following the schematic, metal side up i need to put the second pin in the third hole and the third pin in the second hole for MJE182 and MJE253.

MJE253 should replace TR611.

Is that correct?