Optonica SA-5207 repair

I was playing a CD and listing to the repaired D-7s when the right speakers fuse blew..... Well I got a fuse, and while trying to replace it (the fuse) while going into the fuse holder sparked in my hand with the volume turned down. So I switched the D-7s off and the Jensen's on. The right speaker Jensen was humming pretty loud. So I shut the speakers off, that is when I saw a small amount of the factory smoke came from the receiver.
When checking the board I saw a diode was burnt 458. <-- I assume it's a diode and that is the stencil number next to it on the board.
Will replacing this repair my receiver? as it was working fine until this happened. Thanks
I bought this receiver new.
I can take pictures of the board and burnt diode if it would help?
Added pictures.

I hope these pictures will help someone to help me.
I have a Marantz SR 480 hooked up while I try to get the Optonica repaired.
And with the speakers I have the Optonica sounds a lot better so I will be glad when I get the Optonica back in service.
Thanks for any help I can get.


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Joined 2007
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Or resistor even :) ... looks like it feeds the driver STK. Perhaps see what pin on that STK it goes too (if it does) or if not where it goes.

STK's are prime suspects. Do not connect speaker until you are sure it's OK (Check for DC at speaker outputs).
djk thanks for posting the .pdf file concerning the STK 3042 along with your reply. Is the STK 2240 (picture posted) also available at the same place as the STK 3042?
And I didn't look closely at the .pdf file for a company name or web site to order. And who would you recommend I order it from?
And thanks to every one for there help I really do appreciate it!


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Mooly I can not tell if it goes to the STK 2240 or not, it doesn't look like it to me.
So I have taken two more pictures to see if that might help.

I meant the STK3042 actually as the print runs over in that direction ? If you can't visually trace the print just measure on low ohms (or diode check) from the "R458 marked end" and read down all the pins on the STK one at a time and see if it read short to any pin.
I want to thank all of you for the help I know I could not have done it without you!
Mooly I will check for the short as you suggest.
djk You are great thanks. Resistor same as R457 in the other channel, saves me alot of time as well.
Like I said I love to do this type of stuff and I will learn with the help of nice people like you all!
Again Thanks to you djk, Mooly, & Jaycee.