Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!snorkelwacker!mit-eddie!uw-beaver!ubc-cs!eric!joplin!dleblanc
From: dleblanc@joplin.mpr.ca (David LeBlanc)
Newsgroups: sci.electronics
Subject: Transistor Equivalency (2SC1986 = TIP-41C ?)
Message-ID: <2009@eric.mpr.ca>
Date: 9 Jan 90 00:56:08 GMT
Sender: news@eric.mpr.ca
Reply-To: dleblanc@joplin.UUCP (David LeBlanc)
Distribution: na
Organization: Microtel Pacific Research Ltd., Burnaby, B.C., Canada
Lines: 24

I hope someone out there in net.land can help me.  My SONY integrated
amp just popped a power transistor.  The official SONY replacement part
is a power NPN (2SC1986) which they want $12 for.  The only data book in
which I can find an equivalent part is the Motorola power bipolar book
which states that the TIP-41C is the "Motorola Similar Replacement" (as
opposed to the "Motorola Direct Replacement") which sells at a local 
store for about $1.50.  So far so good.

The question I have is 'How similar will the Motorola part be ?'  Do
output stages of integrated amplifiers tend to rely critically on the
performance specs of the transistors ?  I do not have a schematic of the
circuit but do know that there are not many pot's in the vicinity of the
transistor - this tells me that the circuit is not terribly sensitive
to the transistor's beta (right?).  Any ideas/comments gratefully
accepted.

Notes :

   Amp is the TA-F3A  (approx. 50 W/channel - I think) - NOT what you
   call an audiophile's favorite.

Dave LeBlanc
dleblanc@joplin.mpr.ca
(604) 293-6061