Sony Ps-x75 Important notice re Main MicroProcessor MB8841-2

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brinsmeads
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Sony Ps-x75 Important notice re Main MicroProcessor MB8841-2

Post by brinsmeads » 16 Sep 2013 11:07

If you own a Sony PS-x75 and PS-x65 turntable that doesn’t respond to the push buttons and there is no motor function and power supply voltages are within tolerances

There is a good chance that the 4bit Fujitsu micro processor,
MB8841-209L is faulty. Original Sony Part No…….8.759.982.09
This original Sony encoded IC ( Fujitsu was discontinued in the late 80’s )

Sony advised that in 1991 substitution handbook that this IC was to be replaced
With: Fujitsu……….
MB8841-327L……….. Replacement Sony Part No……….8.759.983.27

There are a number of these for sale in GB on ebay at this time
These micro processors do have a high failure rate and many Sony PS-x75 and
Sony PS-x65 have been dismantled for components because of these
IC’s being unavailable.
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brinsmeads
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 17 Sep 2013 03:28

Also absent in the display will be the word ‘Locked’
And ‘33’ will not change
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Sony PS-x75 display.jpg
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Topherbarrow
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by Topherbarrow » 07 Nov 2013 00:26

Hey Guys,

My name is Topher and I am new to turntables, but have been interested in them for a while. I have recently been given a PS-X75 , but it has this exact issue.

My question is....if I get my hands on this replacement part, how difficult is it to replace?

Any help is greatly appreciated!!

Thanks,
Topher

Cobra2
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by Cobra2 » 09 Nov 2013 17:42


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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 30 Nov 2013 11:24

Not a difficult job to do, it's a 42pin IC
To unsolder, follow safety precautions in Sony PS-x75 service manual

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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 01 Dec 2013 02:13

USA owners of Sony PS-x75
Sears, also do appear to have stock of the MB8841-327 IC albeit costly at $79

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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 01 Dec 2013 05:19

I toyed with the putting a 42 Pin DIL IC socket with gold plated contacts on to the PS-x75 main PCB.
If you felt uncomfortable soldering the MB8841-327 IC directly to the PS-x75 main PCB this may be worth considering

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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 01 Dec 2013 05:28

42 pin ic socket.jpg
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mallikh67
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by mallikh67 » 01 Dec 2013 18:55

hi

i have this ttable and looking for the mb8841327 ic but invain.any one can lead

me where to get this ic

brinsmeads
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 01 Dec 2013 21:47

Try Dalbani UK as suggested by Arne, and Sears USA on Line Sales for sterters

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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by twhtalm » 18 Dec 2013 15:24

Sears is no longer carrying the MB8841-327, found out the hard way by getting a refund. Tried to contact Dalbani and have not heard anything, doubtful that they have this IC anymore. Does anyone have any other leads? Sounds like there are a handful of tables on here besides mine that need this repair.

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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by brinsmeads » 22 Dec 2013 10:23

MB8841-327 Fujitsu IC - For PS-X75, PS-X65, PS-X65C - Sony Part # 8-759-983-27 See original listing


Item condition:New
Ended: Nov 27, 2013 13:18:13 PST
Price: US $39.99
Shipping:
Item location:Camarillo, California, United States
Seller:
wi5connect (340 ) | Seller's other items

mallikh67
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by mallikh67 » 23 Dec 2013 06:18

hi

i am also looking desperately for this ic and sears doesnt have in stock

and the given ebay member also doesnt have in stock. any other genuine source to

grab this ic

Cobra2
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by Cobra2 » 08 Jan 2014 17:26

WANTED: one chip...
reward $ 100

Arne K
NORWAY
(or please help buying this; http://www.searspartsdirect.com/partsdi ... 528&blt=04 -and ship overseas to me)

twhtalm
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Re: Sony Ps-x75 Important notice re Main MicroProcessor MB88

Post by twhtalm » 09 Jan 2014 20:07

Reviewing the service manual I discovered that the MB8841 doesn't do much more than sequence all of the individual operations. Because of this I have decided to use a Teensy++ 2.0 to see if I can replicate the operation of the table. If I am able to do so I have line of sight of a modern direct replacement for the MB8841, which the developer has offered to adapt my program for his hardware. If this works and there are enough people we're looking at under $60 for the direct replacement. Hardware for testing is on the way so it will be 2-3 weeks before I can give you guys an update.

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