Hello, I'm repairing a Technics Se-A3 amp with an hs channel. I have 2 2sa1112 transistors that have a low hfe too low compared to the technical sheet and on the second channel also on the 2sc2592 pair, in your opinion can I replace them without problem with 2sa1306 B and 2sc3298-B?
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Hello
Thank you for all the many answers 😊.
I managed to find equivalents i.e. the 2sa1930 and 2sc5171 in my stock of parts.
Now I also noticed that some transistors 2sc2224 q115 and q116 had also had an hfe of 93 for one and 103 for the other, the datasheet tells me that the hfe must be 180 minimum.
These transistors are not found with their 2sa964A complement, I will have the same question as at the beginning can I replace these transistors with 2sa1306A and 2sc3298A without problems?
Do you have other references for 2sc2224A or 2sa964A that are still available.
Thank you for your answer.
Kind regards
Steven
Thank you for all the many answers 😊.
I managed to find equivalents i.e. the 2sa1930 and 2sc5171 in my stock of parts.
Now I also noticed that some transistors 2sc2224 q115 and q116 had also had an hfe of 93 for one and 103 for the other, the datasheet tells me that the hfe must be 180 minimum.
These transistors are not found with their 2sa964A complement, I will have the same question as at the beginning can I replace these transistors with 2sa1306A and 2sc3298A without problems?
Do you have other references for 2sc2224A or 2sa964A that are still available.
Thank you for your answer.
Kind regards
Steven
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These transistors are suitable as a replacement. I also had to replace this last year because the power amplifier was completely worn out.
Please also check the OA90 diodes and replace the double diodes with 2 *1N4148 in series.
Be sure to check the following resistors on the other board:
R119
R123
R134
R131
82K each. They were clearly wrong on both of my power amplifiers.
Please also check the OA90 diodes and replace the double diodes with 2 *1N4148 in series.
Be sure to check the following resistors on the other board:
R119
R123
R134
R131
82K each. They were clearly wrong on both of my power amplifiers.
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What reference did you replace them with if you remember? Because I don't see too many equivalents available, on the mk2 version they replaced them with 2sc1573 and 2sa879 but those from ebay are not available and I don't I'm not sure if these are real on eBay. I checked all the components on the 2 channels and the resistors and there are the 82k which are not good. 1 measures 83.7k and others 90k, so I replace them all. On the output transistors I only have 1 to click on a pair in an OD-503 and a second with a low hfe of 27, there is an ebay seller who agrees to sell me 2 used ones. I attach the photos of the original transistors that I opened out of curiosity.I'm hesitant about putting the original ones back or replacing them all on the 2 channels, I'm also hesitant about the replacement reference, what do you think of 2sa1943 and 2sc5200? Thank you in advance for your response. Sincerely
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I replaced the OD503 with 2SA1943 and 2SC5200.
I have also converted the circuit board and the heat sink so that you can always install modern types for it.
I have to check the others this evening to see which ones I installed for what.
I have also converted the circuit board and the heat sink so that you can always install modern types for it.
I have to check the others this evening to see which ones I installed for what.
Some news about the Se-A3 amplifier, I talked with the person who sold me this amp and who knows the Technics brand very well, he told me that the OD-503 transistors are in fact 2sa1065 and 2sc2489 Matsushita in a new case. Comparing the datasheet it's impressive, it's exactly the same specifications, too bad it's to3 cases. I looked at the equivalents and the njw0281g are perfect for replacement, I think I'll order those.
I'm sharing the information because I haven't seen it anywhere on the internet, if it can be useful to other people.
I'm sharing the information because I haven't seen it anywhere on the internet, if it can be useful to other people.