2n3055?

[destroyer X]

This one was written on it in red the label "toshiba"

Carlos

[destroyer X]

"toshiba" written in red on it.
]The same last image, a chip detail.

Carlos

[jaycee]

I guess you're unsure if it's a fake or not

Rod Elliot has a picture in his article about fake transistors showing the inside of genuine OnSemi/Motorola transistors:

http://sound.westhost.com/fakes-r1.jpg

from those pictures the 2N3055 you show looks genuine. The biggest clue is the copper baseplate it is mounted on - the fakes usually don't have a copper heat spreader.

[K-amps]

Based on the picture, it looks like a perforated emitter substrate from toshiba....

[destroyer X]

Let friends decide if fake or not....i believe it is fake, and my reasons are:

Was too pretty to be a 2N3055 that i know very well since 1950, this transistor is heavy, strong case, this one was a little bit rouded as a flying source... UFO.

Also 2N3055 never came painted with red ink.

Also the cover never made with this "can" metal... this metal used to make metal can.... to food conservation.... food preservation...long time stock food.... flandres foil because was first discovered and used in France, city of Flandres... this reason the name... not thick, a little week to iron oxide... this one had a thin aluminium surface... alike paint.

Internal 2N3055 is uggly.... is awfull, has a metal table full off parallelled lines.... has old characteristics.

Very difficult to cut, to sand and to damage related to impact

This one was ligth weigth.... with your fingers you can turn it a little... pins are week too..... leads are.

Also the semiconductor chip....is too much small, and covered with some kind of white rubber or silicone material.... real 3055 not!

It cost three units for a dollar... and gain was good...better than 2N3055..... 140 is not common in 2N3055, normally is 30 to 70
gain.

I test it with giant heat sink.... and silicon grease..... and made it work in a supply series transistor..... when reach 3 amperes and 13.8 volts it burns...... standard 2N3055 can hold easy 14 volts from emitter to coletor and 7 amperes continuously.

This one is not.... put it only to show you that this kind of thing is going everywhere.

The non real transistors normally are more pretty than real ones.

regards friends, and take care... thieves are doing their dirty jobs!

Carlos

[Christer]

Carlos,

Maybe I misunderstand you, but do you mean that the "cap"
part of the can is rounded and not like a cylinder and that the
can is made of aluminium? If so, that is no reason to believe
they are fakes. I have Fairchild ones from 70's that are like
that.

[UrSv]

Hasnt every big manufacturer that ever existed made those? Should mean a fair amount of variation would exist. Which would the real ones be?

[Christer]

Probably not every manufacturer has used every type of
TO-3 can there is, but there is nothing fishy with the type
I tried to describe, at least.

[K-amps]

Carlos,

I have seen tons of 3055's from Toshiba. They were all red ink lettered. They all looked like this from the inside....

[destroyer X]

It's easier to find those strange things than good units.

Of course, we can suspect, because of price.... trying to be clever, i was stupid sometimes i bougth those things.

Also to Radio Frequency transmitters, famous 2SC1969 for HF transmitters are false too.

Interesting is that they make better than Matsushita. Transistors is beatifull, brigth shinny, wonderfull metalic surface, mirror polished and chromium covered, and they use better material do print identification. It is easier remove Matsushita numbers than those units.

Problem is that do not work in the 30 Megahertz.... almost no power output.... gain is ok!.... current too, checked it with 5 amperes continuous, but frequency limit is lower, when reaching 10 Megahertz will start to loose power. It is a 10 Megahertz unit inside with same price to make the things more confused.

Sreten, i also remember those Motorola, aluminium cover. The one i put here had some small rounded in the top... and not aluminium, or duraluminium (hard one), this one use the same metal used in old food can. And the difference is alike you put air pressure on it...hi pressure...and the top became rounded as our heads.

Carlos