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 Post subject: Pioneer SA710 Amplifier
PostPosted: 28 Nov 2013, 17:24 
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Joined: 03 May 2011, 15:16
Posts: 183
Location: Romania,Iasi City
Recently I bought a Pioneer SA710 amplifier from someone.. It works very fine. But when I opened it for clean, I found a little "surprise" at final stage.

On one channel were:
2SA1075 (F) (maybe fujitsu from what I read in datasheet) MS-X black case with heatsink
2SC2525 (F) MN-X black case with heatsink

On the other channel were:
2SA1075 (F) PY-G green case with heatsink
2SC2588 (NEC) ROZA black case with heatsink

From what I read the pair is in fact 2SA1075 with 2SC2525 (respectively 1076 with 2526)... the same pair can be found on ebay under 3 formats: case with heatsink green+black (rectangular, similar as a TDA7294), 100% plastic case (rectangular) or another case bigger than TO220...

My question is: why the combination with a 2SC2588? I saw that could have the same power as 2SA1075.. should be repaired by someone and from lack he put this?

Any idea is welcome.


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PostPosted: 28 Nov 2013, 18:30 
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Joined: 08 Aug 2009, 03:11
Posts: 2229
Location: Chilliwack, BC
Hi,

Was likely repaired and the original part was unobtanium. I have to do that with a lot of 70's and 80's amps I repair.

As long as the specs are equal or greater, there will be no problem.

Cheers!

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-= Gregg =-
* Ratings are for transistors - tubes have guidelines*
Home: GeeK ZonE
Work: Classic Valve Design


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PostPosted: 28 Nov 2013, 19:00 
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Joined: 03 May 2011, 15:16
Posts: 183
Location: Romania,Iasi City
In theory..but in practice? The provider (plant) Fujitsu made a pair 2SA1075 and 2SC2525... NEC is another provider (plant). 2SC2588 I don't find exactly its datasheet..

So you tell me that there wouldn't be a problem this "pair"? The power it is the same, also Vce.

I really like this amplifier. Is really a treasure like design and also for functions. I want to buy from ebay a pair or two of Fujitsu transistors..for "backup".
http://www.ebay.com/itm/FUJI-2SC2525-MT ... 53f505be40 (these are like mine's in case with heatsink)
There are also in plastic: http://www.ebay.com/itm/1pcs-2SA1075-1p ... 2a2b4f77e5 and another type of case as I said -> http://www.ebay.com/itm/2SA1075-Origina ... 1c285a3ce6


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PostPosted: 28 Nov 2013, 19:37 
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Joined: 08 Aug 2009, 03:11
Posts: 2229
Location: Chilliwack, BC
andreidaniel wrote:
In theory..but in practice?


I've been a technician for 30 years... subbing works ;)

As long as one isn't getting WAY hotter than the other (serious spec mismatch), don't worry.

Cheers!

_________________
-= Gregg =-
* Ratings are for transistors - tubes have guidelines*
Home: GeeK ZonE
Work: Classic Valve Design


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