Just make sure the parts in one channel are the same, matching would be nice. All the output transistors should be the same in each channel, differences between channels are okay. There are also 470 ohm and 390 ohm parts that warrant inspection, and don't forget the four diodes (H715 ~ H718). Also, inspect (measure!!) the 0.24 ohm resistors, a replacement would be 0.22 ohm, also 10 ohm and 220 ohm resistors in the driver / output circuit. Normally this means shorted output transistors and possibly drivers as well. I think the Toshiba site is better for looking up transistors they produced, Sanyo also has a search-able site. This is from a second source manufacturer, try to buy from the real manufacturer when you do buy. Look at this link to data sheets for 2SC945 to see what I mean. This does depend on the gain range denoted by the letter following the device type (not an A, B or C), they are commonly types R, O, Y, P and L. Looks like a winner, how about 2SC945? 50 VDC, 150 mA, 250 mW and gain from 40 to 700. I call them "the book of lies" and for good reason too. Remember, you are not allowed to use the ECG or NTE parts, nor are you allowed to use either replacement "manual". Now you only need to select a replacement with the same pinout and similar ratings. The following ratings are absolute maximum values except for gain and things like that, those will be typical values.Ģ5 VDC C-E, 200mW (at 25° ambient), collector current is 100 mA maximum and a beta of approx. Just making sure we are talking about the correct parts here.Ī quick look with Google presents the following data for the 2SC371. Those are for H705 and H706? The complimentary parts are H707 and H708 (2SA562Y) and these are the current limiting transistors - right? of course the more expensive the part, the more they can charge the customer for the repair. I used to use 2SD870 in video monitor service - $4.10 at MCM and the NTE89 sub for it is $8.45. In that MCM catalog, the 2SC1328 was 9 cents, while the NTE199 was $1.06. The amp certainly won't meet its power specs or reliability.Īnd the NTE stuff costs more. That NTE power xstr won't match up to anything. If one xstr turns on a bit lower than the others it hogs current, and conversely if one turns on a bit higher, the others do its work. When I have a row of six power xstrs in an output stage, I need them to share current. I work in pro audio, and this is especially important in high power amps. Small-signal Transistors and Diodes Cross Reference Transistors PHILIPS GA TRANSISTORS CROSS REFERENCE COMPETITOR TYPE NUMBER PHILIPS-TYPE-No. They make - or at least supply - a number of transistors, and they list the ones that most closely resemble your parts among those they make. Don't labor under the misconception that the NTE stuff is some sort of exact replacement - it's not.
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