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-   -   Technics SA-202 Stereo Receiver issues (http://www.videokarma.org/showthread.php?t=270983)

Boobtubeman 10-23-2018 11:34 PM

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

vortalexfan 10-23-2018 11:56 PM

Quote:

Originally Posted by Boobtubeman (Post 3205063)
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?

zeno 10-24-2018 06:49 AM

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:smoke:
LFOD !

vortalexfan 10-24-2018 08:53 AM

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?

Boobtubeman 10-24-2018 09:08 PM

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

vortalexfan 10-24-2018 10:14 PM

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.

Celt 10-25-2018 06:36 AM

Good deal, Lucille!

zeno 10-25-2018 08:00 AM

Sounds fixed to me ! Well done. Now put something else on
the bench for us to work on !

73 Zeno:smoke:
LFOD !

Boobtubeman 10-25-2018 10:15 PM

Sounds like nothing outside the shorted chip suffered... BRAVO!!

Time to enjoy the tunes.. :)

SR

vortalexfan 10-25-2018 11:22 PM

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?

zeno 10-26-2018 02:34 PM

Quote:

Originally Posted by vortalexfan (Post 3205154)
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:smoke:
LFOD !

WISCOJIM 10-26-2018 02:51 PM

Quote:

Originally Posted by vortalexfan (Post 3205154)
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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