Hi Walter,
All you can do is buy and try, then identify those vendors who sell fakes. Keep in mind that anyone can run into fakes, it's probably more difficult for them to keep their stock clean. No sense in beating a source down that is normally a good one. Just be fair, as you have been here.
-Chris
All you can do is buy and try, then identify those vendors who sell fakes. Keep in mind that anyone can run into fakes, it's probably more difficult for them to keep their stock clean. No sense in beating a source down that is normally a good one. Just be fair, as you have been here.
-Chris
Why companys do not support DIY electronics groups, these fora do really put knowledge in the world, High end audio in the first place is a discrete community, do not want ic,s and such but pure parts.
Companys see not the importance of it, maybe starting a company making these parts is a market hole who can be filled, special with make them real high end .
regards
Companys see not the importance of it, maybe starting a company making these parts is a market hole who can be filled, special with make them real high end .
regards
Hi kees52,
Due to massive abuse of their samples programs (On-Semi & Fairchild for example), they have closed that down to legitimate designers. To some, audio DIY people are more trouble than they are worth. I can remember a time when ordering samples was reasonable in cost. Now, the golden goose is dead and we have to find distributors that sell the parts we want. Even non-audio parts that I use.
Getting real parts will be even more difficult for those of us who need them. The rest of us will have to be happy simulating circuits.
-Chris
There is no money in it for them.
That isn't always true. Integrated circuits have their strengths and weaknesses. They can perform better than discrete circuits sometimes.
I am afraid that audio is a tiny market, not worth pursuing in economic terms. But face it, surface mount parts are here to stay and folks like On Semi and Fairchild make some of the best transistors. The National Semiconductor collection of companies, plus Linear Technology make the best IC's on average.
Due to massive abuse of their samples programs (On-Semi & Fairchild for example), they have closed that down to legitimate designers. To some, audio DIY people are more trouble than they are worth. I can remember a time when ordering samples was reasonable in cost. Now, the golden goose is dead and we have to find distributors that sell the parts we want. Even non-audio parts that I use.
Getting real parts will be even more difficult for those of us who need them. The rest of us will have to be happy simulating circuits.
-Chris
Oke thanks for the explaining I do agree i that also high end guys has to go smd, I have already a lot of restistors caps in smd form, now to go use them, but I am 58 so eyes get less good, but good glasses wil work, I do think by buy a pc camera who do magnify and so I can do make it.
The J-fets I ded understand was the problem?, I do use them in my amps, also I use tubes in it who do well.
Th alexander amp I have now simulated, this with a opam a integrated one haha, but it is a burr brown opa 627 because not al opamps can be used in this current feedback amp on picture left and a local feedback allfet amp on the right.. I do use here these Jfets, normal transistors are indeed enough to find.
regards
kees
The J-fets I ded understand was the problem?, I do use them in my amps, also I use tubes in it who do well.
Th alexander amp I have now simulated, this with a opam a integrated one haha, but it is a burr brown opa 627 because not al opamps can be used in this current feedback amp on picture left and a local feedback allfet amp on the right.. I do use here these Jfets, normal transistors are indeed enough to find.
regards
kees
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They look like they have been recovered from an assembly.
Maybe because some pre-production samples failed during final testing.
Maybe because some pre-production samples failed during final testing.
The left are rectifier diodes and looks oke, but the igbt,s has much solder on the pins, just testing with big current when pcb ts ready wil give the truth,
regards
Hi !
Anyone ever heard about the MULTICOMP manufacturer ?
I was looking for originals MJ15003 and 2N3773 and I found this manufacturer on the Farnell Store in Brazil
They are around 30% cheaper than On Semi, here the datasheet http://www.farnell.com/datasheets/313115.pdf
Anyone ever heard about the MULTICOMP manufacturer ?
I was looking for originals MJ15003 and 2N3773 and I found this manufacturer on the Farnell Store in Brazil
They are around 30% cheaper than On Semi, here the datasheet http://www.farnell.com/datasheets/313115.pdf
Farnell sells many lines that are marked Multicomp.
Open a datasheet and you see their name again.
Open a datasheet and you see their name again.
Then Multicomp is a Farnell manufacturer ?
So can I buy this transistors, they aren't counterfeit ?
So can I buy this transistors, they aren't counterfeit ?
Yes SMT parts are here to stay so instead of fighting it I just learned how to work with them. I actually find them easier to work with for proto typing. They are much easier to get off a board than fighting with plated through holes. It's worth surrendering to the technology and learning how to work with SMT even the tiny tiny stuff.
A good pair of tweezers and a steady hand.
Hi David,
Certainly! But those younger folks have the advantage as their eyes haven't gone south yet.
They are easier to prototype with as the number of drilled holes can be drastically reduced. Just in time for me, the pattern transfer products have made PCBs a possibility for me. I would be toast otherwise!
The one thing we still have to get use to is the 350 mW power limit as opposed to the 500 mW average for TO-92 devices. Also, coupling transistors together thermally is a little more difficult now.
You forgot something critical for using surface mount stuff. Freedom from a sneeze! It's all over when that happens. Matching parts is also more difficult. Can be done, but it is a real PITA to accomplish.
-Chris
Certainly! But those younger folks have the advantage as their eyes haven't gone south yet.
They are easier to prototype with as the number of drilled holes can be drastically reduced. Just in time for me, the pattern transfer products have made PCBs a possibility for me. I would be toast otherwise!
The one thing we still have to get use to is the 350 mW power limit as opposed to the 500 mW average for TO-92 devices. Also, coupling transistors together thermally is a little more difficult now.
You forgot something critical for using surface mount stuff. Freedom from a sneeze! It's all over when that happens. Matching parts is also more difficult. Can be done, but it is a real PITA to accomplish.
-Chris
Ya sure. Lots of magnifying stuff around for us old foggies.
So 1W isn't enough for you in a 3904. Just one example.
Since this is off topic I'll make this the last one.
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This is my transistors collection, some opinion about they ?
Original or counterfeit ?
The TIP3055 looks like original in my opinion, but the 2SC5200 and 2SA1943 looks like fake
The others I can't identify..
Thanks
Original or counterfeit ?
The TIP3055 looks like original in my opinion, but the 2SC5200 and 2SA1943 looks like fake
The others I can't identify..
Thanks
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
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I believe some of the Toshiba 2SC5200/2SA1943 are the real deal. Look at the top edge, do they have two small rough areas like some tabs were removed. The print etching can be hard to read on these. There is a schematic on this site for a test fixture to test these at some serious power levels, don't remember which forum though.
MI
Indeed, better looking at the first page pictures my 2sc5200 seem real. I'll test the hfe and I will tell the result later.
I suspected them because I paid a low price, while the "reals" are sold around R$ 15.00 I paid them around R$ 8.00 ( I don't remember the exact values, just an example)
For the other transistors, any thoughts?
