Do you think that these are reputable? Or should I stick with mouser and Digikey
2Pair 2SB688 & 2SD718 SANKEN Transistor D718 & B688 NEW: Amazon.com: Industrial & Scientific
2Pair 2SB688 & 2SD718 SANKEN Transistor D718 & B688 NEW: Amazon.com: Industrial & Scientific
I would not trust them. As far as I know, Sanken stopped production many years ago (someone correct me if that's not correct). NOS is OK but they're more likely counterfeit. The part numbers I posted are new parts that can be purchased from reputable, authorized distributors.
Places like ebay, amazon, etc are great if you want to buy a fishing hat or an old/vintage doo-dad but for electronic components, especially semiconductors, I recommend that you buy from those authorized by the manufacturer to sell their products.
Places like ebay, amazon, etc are great if you want to buy a fishing hat or an old/vintage doo-dad but for electronic components, especially semiconductors, I recommend that you buy from those authorized by the manufacturer to sell their products.
Ok thanks Perry
Are these 2 good?
FJA4213RTU ON Semiconductor / Fairchild | Mouser
FJA4313RTU ON Semiconductor / Fairchild | Mouser
Is the
FJA4213 the 2SB688
and
FJA4313 the 2SD718
Are these 2 good?
FJA4213RTU ON Semiconductor / Fairchild | Mouser
FJA4313RTU ON Semiconductor / Fairchild | Mouser
Is the
FJA4213 the 2SB688
and
FJA4313 the 2SD718
So I changed out the 2 transistors and the amp powers up and comes out of protection. I checked the amp and I have audio being outputted from all channels except the front right. It seems like there is some audio but it is really low compared to the front left. All other channels play normal. Any ideas?
Do you have a scope?
If the signal is clean, the problem is virtually always in the preamp section.
Try this... Bridge the low channel with another channel. Does the bridged speaker play at the same level as a single good channel?
Is the audio still clean?
Be careful if the transistors are not clamped down. They can overheat and fail in just a few seconds.
If the signal is clean, the problem is virtually always in the preamp section.
Try this... Bridge the low channel with another channel. Does the bridged speaker play at the same level as a single good channel?
Is the audio still clean?
Be careful if the transistors are not clamped down. They can overheat and fail in just a few seconds.
If it's still clean, that would generally indicate that final section of the low channel is working.
I see what appears to be 4 green (?) caps, one per channel. Is that right?
If so, those could be the coupling capacitors. If so, if you drive a sine wave signal into the various channels, you should see the signal on those. Check this by driving a signal into the amp and measure the AC voltage on those caps. Is it low on the low channel's cap?
I see what appears to be 4 green (?) caps, one per channel. Is that right?
If so, those could be the coupling capacitors. If so, if you drive a sine wave signal into the various channels, you should see the signal on those. Check this by driving a signal into the amp and measure the AC voltage on those caps. Is it low on the low channel's cap?
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