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2275 Outputs

R

rmorano

Active Member
Hello;

Working on a 2275 that has one power amp with motorola and one with toshiba outputs. (must have been repaired at some point)

Now the Motorolla output has shorted and most likely taken out the differential transistors as well.

What is a good replacement source for the SJ2517 / SJ2518 Motorolla

or

Toshiba 2SB554 / 2SD424 outputs

I want to fix the dead amp and end up with a match on both left and right sides.

Considering using NTE replacements in both sides


R.
:tears:
 
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On Semi MJ21193/94 or MJ21195/96 are the obvious choices for outputs.
You should check for other problems before just plugging the new parts in.

Tom
 
Thanks for the quick response. I think another transistor is blown also, one of the two on the heatsinks that are board mounted.

Who stocks On Semi ??
 
ONSEMI MJE 15031 / MJE 15032 or 15033/15034 are a good choice as drivers (the transistors on the little onboard heatsinks)

Helmut
 
Great will be ordering them from Mouser, should not be too bad, checked pricing and they are reasonable

Thanks to all
 
Hello;

checked cross referance for the SJ2517 / 18 and cant come up with MJ21193 /94 as a suitable replacement. Am I missing something ? Has someone used the MJs in 2275 ??
 
rmorano said:
Am I missing something ?
Click to expand...
Apparently, yes.

The classic metal TO-3 package is going away. There are only a couple of reliable substitutes, all made by On-Semi: (exception to the rule)(Edit: Looks like that exception is being discontinued)

MJ21193 & 94
MJ21195 & 96
MJ15024 & 25
MJ15031 & 32
MJ15001 & 02
MJ15003 & 04
MJ15011 & 12
MJ15022 & 23
MJ15015 & 16


Any out-of-production Japanese device (such as the Toshiba's you mention) are more than likely Chinese counterfeit, and NTE's are not an option for anyone who is doing quality work. The first four mentioned here (MJ21193 ~ 96) are the best choice for audio.

All parts must be purchased from a reseller who sources directly from the manufacturer, as there are plenty of counterfeit On-Semi devices out there too.
 
Last edited:
Yes I was very confused with all the numbers. Will be going foward with my Digikey order for the MJ / OnSemi products.

Just want to be absolutly sure, my 2275 is too good to mess up. One side has Motorolla outputs and the other side (which had work by someone) has the Toshiba

Going to replace all four with MJ's and also the drivers on both boards

Thanks again
 
Some great info here and just maybe I can get my question answered.
The left channel of my 2270 has the following transistors installed: SK9134 and SK9136.
Can someone reference which "On Semi" replacement transistor is a direct replacement for the SK9134 and SK9136? Appreciate the info.
Mike
 
MikeED said:
Some great info here and just maybe I can get my question answered.
The left channel of my 2270 has the following transistors installed: SK9134 and Can someone reference which "On Semi" replacement transistor is a direct replacement for the SK9134 and SK9136? Appreciate the info.
Mike
Click to expand...

Never heard of sk9136.

2sk and 2sj are Mosfets and do not belong in a 2275.
 
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