Transistor Replacement search

Cmndr Brain

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I need help finding a suitable replacement for 2 transistors that are obsolete. Hoping the community can help.
I've attached 2 images of the transistors and the specs.
My research has yielded a couple of options.
For the 2SC3279 -> Fairchild KSC5019 or ONSemi 2SB926
For the A1300 -> OnSemi 2SD1246
I've found these replacements on Mouser and Digikey, yet all 3 replacements are bulk buys only. Don't really want to pay $1000+ for 1000 transistors
when I only need 4 of each. Can anyone point to compatible replacements that are reasonably priced and can be purchased. Ebay sometimes has
"originals" but you never know and some vendors sometimes want $15ea. I can risk it, but I'd like to find a reputable place first and if not, risk the ebay.

tr1.jpg tr2.jpg
 
I need help finding a suitable replacement for 2 transistors that are obsolete. Hoping the community can help.
I've attached 2 images of the transistors and the specs.
My research has yielded a couple of options.
For the 2SC3279 -> Fairchild KSC5019 or ONSemi 2SB926
For the A1300 -> OnSemi 2SD1246
I've found these replacements on Mouser and Digikey, yet all 3 replacements are bulk buys only. Don't really want to pay $1000+ for 1000 transistors
when I only need 4 of each. Can anyone point to compatible replacements that are reasonably priced and can be purchased. Ebay sometimes has
"originals" but you never know and some vendors sometimes want $15ea. I can risk it, but I'd like to find a reputable place first and if not, risk the ebay.

View attachment 842563 View attachment 842564

I don't know if it's exactly what you're looking for, but try these:

Be careful with Rochester. They typically have large minimum orders. In this case it shows as 100 min but you can add 1 to your cart.
So...is that 1 unit for $0.17/ea? Or is it 1 bulk of 100 for $0.17/ea ($17.18 total)? I don't have an account, so I can't find out.

???
 
I don't know if it's exactly what you're looking for, but try these:

Be careful with Rochester. They typically have large minimum orders. In this case it shows as 100 min but you can add 1 to your cart.
So...is that 1 unit for $0.17/ea? Or is it 1 bulk of 100 for $0.17/ea ($17.18 total)? I don't have an account, so I can't find out.

???

Rochester is worse than that... IIRC, it's usually a $250 minimum per line item.

$0.17 transistor? Buy 1500 :)
 
Damn, I have a Transistor substitution book from 1978 that's come in super handy for me before, and neither one of these are in it.
Probably came out later.
 
Mouser suggests ZTX649, KSC2328AYTA, or ZTX649STZ... I did not check the pinouts tho
Mouser Part Number,Mfr Part Number,Mfr.,Datasheet,Availability,Pricing,RoHS,Lifecycle,Product Detail,Technology,Mounting Style,Package / Case,Transistor Polarity,Configuration,Maximum DC Collector Current,Collector- Emitter Voltage VCEO Max,Collector- Base Voltage VCBO,Emitter- Base Voltage VEBO,Collector-Emitter Saturation Voltage,Pd - Power Dissipation,Gain Bandwidth Product fT,Minimum Operating Temperature,Maximum Operating Temperature,Series,Packaging
522-ZTX649,ZTX649,Diodes Incorporated,https://www.diodes.com/assets/Datasheets/ZTX649.pdf,"4,702 In Stock","=""$1.28""",RoHS Compliant,,https://www.mouser.com/ProductDetai...49&utm_content=Diodes-Incorporated,Si,Through Hole,TO-92-3,NPN,Single,"=""2 A""",25 V,35 V,5 V,230 mV,1 W,240 MHz,- 55 C,+ 200 C,ZTX649,Bulk
512-KSC2328AYTA,KSC2328AYTA,onsemi / Fairchild,https://www.mouser.com/datasheet/2/308/1/KSC2328A_D-1810317.pdf,"5,420 In Stock","=""$0.55""",RoHS Compliant,End of Life,https://www.mouser.com/ProductDetai...YTA&utm_content=onsemi-/-Fairchild,Si,Through Hole,TO-92-3,NPN,Single,"=""2 A""",30 V,30 V,5 V,2 V,1 W,120 MHz,,+ 150 C,KSC2328A,Ammo Pack
522-ZTX649STZ,ZTX649STZ,Diodes Incorporated,https://www.diodes.com/assets/Datasheets/ZTX649.pdf,"1,160 In Stock","=""$1.29""",RoHS Compliant,,https://www.mouser.com/ProductDetai...TZ&utm_content=Diodes-Incorporated,Si,Through Hole,TO-92-3,NPN,Single,"=""2 A""",25 V,35 V,5 V,230 mV,1 W,240 MHz,- 55 C,+ 200 C,ZTX649,"Reel, Cut Tape"
 
What is it used for, or what is it found in?
It's for an RC car for a friend. He ran it through a puddle and *kaput*. He retired and is currently sailing around "the great loop". He would like it fixed to donate to a less fortunate child for the holidays, Toys for Tots. I'm just trying to getting working again.

Thanks for the information guys. I'll check out some of the links and see if any will work.
rc1.jpgrc2.jpg
 
Rochester is worse than that... IIRC, it's usually a $250 minimum per line item.

$0.17 transistor? Buy 1500 :)
Yeah, I saw Rochester and found out about the minimum order. Damn! You wouldn't need $245 worth of transistors would you?
 
NpN or PnP... isn't there something "Standard" and less obscure that might fit the bill? Now that the application is understood, it needn't be rocket science...

Are there any nerds in the house that can come up with a common and readily available substitute that meets or exceeds the specs of the OG silicon without resulting in a thousand spares?

Just askin' fo a friend...

~D
 
NpN or PnP... isn't there something "Standard" and less obscure that might fit the bill? Now that the application is understood, it needn't be rocket science...

Are there any nerds in the house that can come up with a common and readily available substitute that meets or exceeds the specs of the OG silicon without resulting in a thousand spares?

Just askin' fo a friend...

~D
That could be. Would need data sheets for the devices but more importantly a schematic for the circuit.

A person can always start with 2n3904 and 2n3906 and just go for it. But It's better to understand what you're replacing first.
 
That could be. Would need data sheets for the devices but more importantly a schematic for the circuit.

A person can always start with 2n3904 and 2n3906 and just go for it. But It's better to understand what you're replacing first.
I get that.... however, the OP did post the data at the front end of this post that went unanswered for several days before I poked back to the top...

~Dylan
 
I get that.... however, the OP did post the data at the front end of this post that went unanswered for several days before I poked back to the top...

~Dylan

I don't know. It looks like a ~1-day response to me. That's pretty good customer support in this day and age! :ROFLMAO:

But you are correct sir. He did post transistor summaries at least. But I forgot about it because I first saw the OP's post on my phone. I don't bother trying to get or read datasheets on my phone.

I'd still feel much better about choosing a different type with an application schematic in hand. Is it used as a switch? A linear amplifier? A buffer? An oscillator? Is it being operated forward or backward? Will the replacement be operating in it's Safe Operating Area? Etc...

I'm sitting at a real computer now and I looked at the full datasheet for the 2SC3279 (Toshiba). Man that's kind of a beast of a transistor. 2A? 750mW? In that tiny package? Wow. Decent SOA too.

@Cmndr Brain try looking at the Chinese distributors. They will probably have a few pieces lying around in stock and they are usually happy to sell in lower quantities. It might only be "Asian Suppliers" aftermarket copies, but sometimes you'll get lucky. And hey...Toshiba is an asian supplier too! Of course you'll have to pay extortionist shipping prices and now the tariffs will kick you in the teeth. But it's another option and it might actually be cheaper than Rochester when all is said and done.
 
I don't know. It looks like a ~1-day response to me. That's pretty good customer support in this day and age! :ROFLMAO:
My bad... I stand corrected.... it was all day without a response.... not "several days"... but in all fairness, It had sunk down rather far in the "new posts" list.

OPs post was of interest to ME, and nobody had responded in my "entitled impatient time frame"🤣, so I felt compelled to pop it back to the top of the list to solicit some "sleazy need fixin' attention" I was feeling I needed at the time! lol

-D
 
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@Cmndr Brain try looking at the Chinese distributors. They will probably have a few pieces lying around in stock and they are usually happy to sell in lower quantities. It might only be "Asian Suppliers" aftermarket copies, but sometimes you'll get lucky.
But here's the rub... as OP stated... it's a chance ordering from FleaBay, Scamazon, Ali, et al... how does one make the best roll of the dice to not procure counterfit junk from said suppliers, as well as "the asian sources" you suggest. It's not like any of "those guys" are signed up with the "anti counterfit parts" so called "registries".

It's been my experience that it is difficult, at best, to find statements to the effect of "we stand to fight the proliferation of counterfit parts" type statements... even from the "well known/established" suppliers.

We take it on faith that the "big 3"... or 4 suppliers make best efforts to guard against counterfit parts(but even the big guys get bit sometimes)... but that info isn't readily available from the "smaller" suppliers.

What strategies have you found to be more successful at steering your purchase orders away from counterfit parts. Is there some master list of "good" suppliers that I've not yet found?

~D
 
But here's the rub... as OP stated... it's a chance ordering from FleaBay, Scamazon, Ali, et al... how does one make the best roll of the dice to not procure counterfit junk from said suppliers, as well as "the asian sources" you suggest. It's not like any of "those guys" are signed up with the "anti counterfit parts" so called "registries".

It's been my experience that it is difficult, at best, to find statements to the effect of "we stand to fight the proliferation of counterfit parts" type statements... even from the "well known/established" suppliers.

We take it on faith that the "big 3"... or 4 suppliers make best efforts to guard against counterfit parts(but even the big guys get bit sometimes)... but that info isn't readily available from the "smaller" suppliers.

What strategies have you found to be more successful at steering your purchase orders away from counterfit parts. Is there some master list of "good" suppliers that I've not yet found?

~D

If you don't personally know Sam (the guy that makes all of these parts in his shed) then there's never a guarantee of legit parts. Larger distis like Digikey and Mouser, Arrow, Avnet, etc. are pretty good about stuff because they buy directly from Sam. Otherwise, it's always a gamble. Maybe try Win Source? They're kind of like Quest or Rochester...they have a lot huge assortment of non-authorized inventory and obsolete parts. Meaning they bulk buy parts from Sum Guy and he claims they were made by Sam.
 
Try this site also

This company has a lot of the old transistors (Orig 2SC3279 here)

Also 2SC3205, 2sd1207

Australia post have ceased all mail to the US, so it would have to be courier

But you could use the first link to find one of them transistors locally hopefully
 
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