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Transistor Substitutions

Fitzer said:
Anybody know of a modern substitution for a D880 in TO-220 packaging with the same pinout? It's in a tight spot with a dedicated heatsink so the pinout has to be the same so that it can screw into the heatsink properly.
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TO-220 is from left to right Base Collector Emitter. The 2SD880 is exactly the same. @avionic gave you the exact replacement. :thumbsup:
 
Does anyone happen to know if there are replacements available for these transistors labelled as...?
C2602 31G
BC559B PHP305
BC599B PHP310
They're in the phono section of a NAD 3020A.IMG_7682 copy.jpg 961619d1624347155-nad-3020a-replacement-balance-pot-bypass-balance-pot-3020a-phono-jpg-1.jpg
 
Thanks Redk9258.
So, maybe I should get some KSC1845FTA and match the best pair?. Would they likely be better, worse, virtually indistinguishable?
Anybody able to recommend what I should get for the:
BC559B PHP305
BC599B PHP310
 
Just going by what’s on the board already, I’ve owned since new in the early 1980’s.
Here’s another photo showing the printing on the transistors.
 
BC559 are still in stock at Mouser, ergo no need to replace them with anything different. There is no BC599 in the NAD 3020. PHP is the manufacturer, Philips.
 
Hifibythekg said:
Does anyone know the relevance of the suffix
“PHP305” and “PHP310” and what should then seek out in a modern replacement?
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Those are just manufacturing codes, Philips in this case, and date code 310. the BC559B is the one in the proper gain (hFE or Beta) group. The B is that designation.
 
Hi friends
Sorry if my question sounds repetitive.

I need to replace 2sa720 and 2sc1318 transistors on my marantz 4270.
I read here that I can use sa1013 instead of a720, and sc2383 instead of c1318.
My question is: Are these substitutes low noise too?
There are other transistors I can use to replace:
a992/ c1845
a1015/c945/
....or others?

What would be the best choice to replace sa720 and sc1318?

greetings, and thanks for the help.
 
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A a992/ c1845 combo from a reputable seller pretty much alway does a better job then the originals. And yes they are low-noise low-leakage.

Mind the polarity!
 
in a Rotel RB-970BX power amp Q613 / Q614 are 2sa1208 in the service manual but the right q614 in the amp is an a1370 the other q613 is an a1208 and it has failed. what commonly available transistor would replace these? thanks
 
theDG said:
in a Rotel RB-970BX power amp Q613 / Q614 are 2sa1208 in the service manual but the right q614 in the amp is an a1370 the other q613 is an a1208 and it has failed. what commonly available transistor would replace these? thanks
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I think KSA1381 would work.
 
The original devices are rated for Vce of 160V. To get that voltage rating it may be ncessary to change to a TO-126 package in a "modern" replacement device, such as the KSA1381F suggested previously.

However, my suspicion is that the ± rail supplies of the amp are under 50V. That is based upon the ratings of the main filter caps in the unit, but you can verify that by measurement.

If the voltage is less than ± 50V that would open the possible replacements to numerous other devices that may not create the installation problems of fitting the larger leads or a TO-126 package into the PCB holes designed for TO-92s. Those coul be KSA931Y.
 
If the rail voltage is below ± 50V, the BC640 would survive. One potential problem is that it has a minimum gain rating of less than half that of the original (40 versus 100). It also is not necessarily categorized as a low-noise amp. Its complementary device (BC639-16) is even more marginal.
 
Is there a new substitute for the 2sc869? The KSC2310 seems to be obsolete. This for Q1 and Q2 in the SA-9500 II switch board AWS-109.

The service manual list the 2SC869 with the 2SC1649 in brackets. The sub for the 1649 is the KSC1845, so can the 1845 then be used for Q1 and Q2? I did pull 869's out of the board though.

EDIT: Think I found the answer. In reference to an SX-1250, Mark referenced 512-KSC2383YTA as a replacement.
 
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