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  #16  
Old 10-24-2018, 12:34 AM
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Boobtubeman Boobtubeman is offline
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Reminds me of a FISHER rack system amplifier with STK-0080 chips. Had a shorted Left when i got it, and i put in a new chip. A couple months later, while rocking the house, the left chip let go and smoke rolled out of the left speaker. Turns out, the bias resistor (white square 3 leads near the chip) was out of whack and it led to the demise of the new chip. Be sure to test them to make sure the prior shorted chip didnt effect the resistor..

SR
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  #17  
Old 10-24-2018, 12:56 AM
vortalexfan vortalexfan is offline
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Quote:
Originally Posted by Boobtubeman View Post
Reminds me of a FISHER rack system amplifier with STK-0080 chips. Had a shorted Left when i got it, and i put in a new chip. A couple months later, while rocking the house, the left chip let go and smoke rolled out of the left speaker. Turns out, the bias resistor (white square 3 leads near the chip) was out of whack and it led to the demise of the new chip. Be sure to test them to make sure the prior shorted chip didnt effect the resistor..

SR
OK Where would the Bias Resistor be in my Receiver if it has one?
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  #18  
Old 10-24-2018, 07:49 AM
zeno zeno is offline
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One last thing to do is compare the DC voltages on the chips & be sure
they are the same. That will smoke out almost any other problem.
Then run it for a while checking how warm the chips run. Should be
about the same.

73 Zeno
LFOD !
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  #19  
Old 10-24-2018, 09:53 AM
vortalexfan vortalexfan is offline
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Ok, will do. Someone mentioned a bias resistor, was there a bias resistor in this unit? If so what's the number of it on the schematic?
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  #20  
Old 10-24-2018, 10:08 PM
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Boobtubeman Boobtubeman is offline
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They should be very close to the chips (if equipped) they resemble those white, square power resistors.. Basically, check resistors that connect to the chip nearby if you dont see any white power resistors. Zeno covered it best, just do some comparative measuring and make sure everything is close to spec..

SR
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  #21  
Old 10-24-2018, 11:14 PM
vortalexfan vortalexfan is offline
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Well I ran the stereo receiver for about a half hour earlier today, and it seemed to run like it should, and I measured the temperature of the chips and the hottest the replacement chip got after a half hour of running at about quarter volume was about 85 degrees Fahrenheit and the chip that was still good in there that was original got up to about 90 degrees Fahrenheit. But nothing out of the ordinary.
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  #22  
Old 10-25-2018, 07:36 AM
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Celt Celt is offline
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Good deal, Lucille!
__________________

Let me live in the house beside the road and be a friend to man.
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  #23  
Old 10-25-2018, 09:00 AM
zeno zeno is offline
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Sounds fixed to me ! Well done. Now put something else on
the bench for us to work on !

73 Zeno
LFOD !
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  #24  
Old 10-25-2018, 11:15 PM
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Boobtubeman Boobtubeman is offline
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Sounds like nothing outside the shorted chip suffered... BRAVO!!

Time to enjoy the tunes..

SR
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  #25  
Old 10-26-2018, 12:22 AM
vortalexfan vortalexfan is offline
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OK So I'm thinking of selling this receiver but not sure what I should sell it for, what would be a reasonable asking price for this receiver now that its been properly repaired and is in proper working order?
I was thinking somewhere between $75-$100 does that sound about right, or am I way off in the value of this receiver?
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  #26  
Old 10-26-2018, 03:34 PM
zeno zeno is offline
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Quote:
Originally Posted by vortalexfan View Post
OK So I'm thinking of selling this receiver but not sure what I should sell it for, what would be a reasonable asking price for this receiver now that its been properly repaired and is in proper working order?
I was thinking somewhere between $75-$100 does that sound about right, or am I way off in the value of this receiver?
Look at past E-bay sales. Thing is nowadays I dont think you can even
buy a stereo (non surround ) until the super high end stuff. Anything
cheap will be Chi-Com junk. I think a C-note is very fair for all. Also
if you plan to sell more give a guarantee, 30 or 60 days.

73 Zeno
LFOD !
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  #27  
Old 10-26-2018, 03:51 PM
WISCOJIM WISCOJIM is offline
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Quote:
Originally Posted by vortalexfan View Post
OK So I'm thinking of selling this receiver but not sure what I should sell it for, what would be a reasonable asking price for this receiver now that its been properly repaired and is in proper working order?
I was thinking somewhere between $75-$100 does that sound about right, or am I way off in the value of this receiver?
https://www.ebay.com/sch/i.html?_fro...lete=1&_sop=16
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