2sc1451 transistors
- Thread starter reddish75
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2SC1451 —> KSC3503 (information from a current thread in this sub forum).
http://www.mouser.co.uk/ProductDetail/Fairchild-Semiconductor/KSC3503DSTU/?qs=sGAEpiMZZMshyDBzk1/Wi8oN7VHZ91OkBLcRKpIYUPA=
Mouser Part No: 512-KSC3503DSTU
http://www.mouser.co.uk/ProductDetail/Fairchild-Semiconductor/KSC3503DSTU/?qs=sGAEpiMZZMshyDBzk1/Wi8oN7VHZ91OkBLcRKpIYUPA=
Mouser Part No: 512-KSC3503DSTU
Just happened to be making my own look-around for 2SC1451 replacements, and I found KSC2330 attractive. Plenty of voltage and power handling in a convenient package (TO-92L, the "L" evidently meaning "long"). Currently in stock at Mouser in the Y beta grade (120-240). Typical 50MHz fT and 4pF cOB - compared to what the web says about 2SC1451, that's a little low, and a perfect match, respectively.
Now I just need to decide whether I deem 2SC1451s a should-be-replaced item. In my own experience, they aren't as troublesome as the they seem to be in the collective AK experience.
chazix (doing a little maintenance on my workhorse SA-9500)
Now I just need to decide whether I deem 2SC1451s a should-be-replaced item. In my own experience, they aren't as troublesome as the they seem to be in the collective AK experience.
chazix (doing a little maintenance on my workhorse SA-9500)
FootFungus
Super Member
There are still real 2SC2632 floating around (Bdent). Those are the previously mentioned 2SC1953 dies in the slightly less beefy TO-92L package.
In a lot of applications (700C, for instance), the C1451/52 is used in locations where they are running close to the maximum Pd. I'd not be using a TO-92 or 92L part in those locations.
So, if you're not sure about your dissipation requirements, use a TO-126 and sleep easy.
So, if you're not sure about your dissipation requirements, use a TO-126 and sleep easy.
EchoWars, would you suggest the KSC3503 over the KSC2383 as a substitute for the 2sc1451/1452 in a Pioneer Exclusive C3? The headphone amp ass'y is quite noisy, and the electrolytics have already been swapped out. I've read on another C3 thread that someone had success swapping out the 1451's.
Just want to make sure I choose the most optimal substitute currently available. Thank you in advance!
EchoWars, would you suggest the KSC3503 over the KSC2383 as a substitute for the 2sc1451/1452 in a Pioneer Exclusive C3? The headphone amp ass'y is quite noisy, and the electrolytics have already been swapped out. I've read on another C3 thread that someone had success swapping out the 1451's.
Just want to make sure I choose the most optimal substitute currently available. Thank you in advance!
Another Zombie thread...
Don't hold your breath waiting for a reply from EchoWars.. Glenn has not been on AK since May of 2017..
Oof. Thanks for the heads up!
I think I'll just go with the KSC3503 in this case and see how it goes.
Sorry for digging up old threads here. Was hoping it'd maybe help others in the future with Pioneer restorations.
Your noisy headphone amp assy in a C3 doesn't USE the 2sc1451's....
It DOES however, use 2sa725 transistors - which fail out as VERY noisy.
I see other 2sc1451's in the C3, and upon first glance,
enough exceptions that I would have to very carefully calculate out each of them and the expectations of that operating position. Looking for gain sensitive locations.
Frankly, I would leave those all in-place. I don't think the circuit conditions that contribute to the death of the 2sc1451( i.e. as found in Pioneer's power amp VAS stages) are present in these.
Your noisy headphone amp is caused by the Q1-Q4 2sa725 transistors.
It DOES however, use 2sa725 transistors - which fail out as VERY noisy.
I see other 2sc1451's in the C3, and upon first glance,
enough exceptions that I would have to very carefully calculate out each of them and the expectations of that operating position. Looking for gain sensitive locations.
Frankly, I would leave those all in-place. I don't think the circuit conditions that contribute to the death of the 2sc1451( i.e. as found in Pioneer's power amp VAS stages) are present in these.
Your noisy headphone amp is caused by the Q1-Q4 2sa725 transistors.
You know, I saw the 725's on the schematic and wondered if those have a tendency to get noisy (like those pesky 2SA798 double PNP's). Seems I missed that. So, thank you for taking a closer look for me (and anyone else who stumbles upon this thread working on a C3 may benefit)!
Coincidentally, I picked up a Pioneer M4 Class A power amp alongside the C3. But, it appears there was already some minor work done to the amp. I noticed some of the problematic transistors were swapped already, and some electrolytics swapped out. They used some Jamicons, which I've heard mixed experiences from others.
Either way, it's not particularly noisy (yet). He/she may have already swapped out the 2SC1451's in that unit. I'll probably found out in due time.
Thanks again for taking a closer look, markthefixer. Happy Holidays.
