Motorolla 2N3055 Real or Fake?

Guys, im looking for a few 2N3055  for a few 283 cards, and i came across these 3 links -

http://cgi.ebay.com/2x-10-2N3055-MJ2955-AUDIO-AMP-TRANSISTORS-TO-3_W0QQitemZ390050288947QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad0cf1533&_trksid=p3286.c0.m14  (Hong Kong?!!)

http://images.google.ie/imgres?imgurl=https://chinaimportexport.wikispaces.com/file/view/Sell_MJ15024,MJ15025,2N3055,MJ15022,MJ15023_Integrated_Circuits_Manufacturer_exporting_direct_from_China.jpg&imgrefurl=https://chinaimportexport.wikispaces.com/Sell%2BMJ15024,MJ15025,2N3055,MJ15022,MJ15023%2BIntegrated%2BCircuits%2BManufacturer%2Bexporting%2Bdirect%2Bfrom%2BChina%3Ff%3Dprint&usg=__5sN3GB7DuNORUKW3dMEbMYIKYZ0=&h=480&w=640&sz=103&hl=en&start=19&sig2=Lv3XvSN69DxWl5JG7T5UCg&um=1&tbnid=CBSA_6imXSB8bM:&tbnh=103&tbnw=137&prev=/images%3Fq%3DOn%2B2N3055%26hl%3Den%26safe%3Doff%26um%3D1&ei=RzudSsadHNbisAbC75HCAQ  (China with this amount of nos?!!!)

http://cgi.ebay.com/2N3055-Motoro-100V-15A-117W-TO3-Power-Transistor-2SD175_W0QQitemZ370253903270QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5634da35a6&_trksid=p3286.m20.l1116


Can you guys spot the fakes?


Im not overly confident with the chiniese guys, as there probally re-badged.


Is there any real NOS Motorolla 2N3055 left.....?

There are no guarantees. All could be real or all could be fake. I am inclined to ask how these parts would end up in China? Motorola only made TO-3s in the US or near the end in their last TO-3 factory in Mexico, until they sold that factory and got out of the business maybe a decade ago or more ago.

I am tempted to ask why bother? The original part was slower than dirt... but I've learned not to ask such silly questions around here.

JR

They all look fake to me.  I've made power amps back in my teenage years using 2N3055/MJ2955s, so I'm familiar with how they look.

The photos above doesn't look like what I used 20 yrs ago.

http://sound.westhost.com/counterfeit.htm

http://www.diyaudio.com/forums/archive/index.php/t-3884.html

for some background

That is not Motorola can unless they changed it in later years. The plinth and the lid had different surface finish on Motorola.  I suspect it is what we used to call "a potato stamp".  I also built a lot of stuff with 2N3055 in late 70s. When I look back now I agree with John but in those days I did not really know better.

Thanks for the info guys,


I think im going to get a few ON Semi 2N3055's from a reputable dealer like Mouser/Digikey. It may cost me a few quid more but for peace of mind i suppose its worth it.


Dfer

FWIW any reputable transistor company probably couldn't make a transistor as bad as the real 3055s if they tried using modern process fab. Look at the spec sheets they probably have better Ft etc. I suspect it's just a catch all part number for bottom of the heap power NPNs

JR

so is everybody using fets nowadays so that we are stuck with no good sub for the leaky 3055?

maybe thats the secret, the edc into the primary of the output, take out the bypass and let the 3055 bias the inductance right out of the transformer.
got it.

I've just analyzed/curve-traced some real old Motorola 2N3055 vs recent ON.
The old are more capacitive, less Beta, less linear at low current, more linear at high current [I mean, more than 200 mA].
I've read the Geoff Tanner post about better hi-freq response of the Motorola, used because of that in Neve 183/283..
But maybe its really also the non-linearity that matters?

I know, I'll try both with the 1290 boards and will use my ears.

i got a few original ones from ex-mod(ministry of defence) source, it will probbaly be ur best bet in the uk.

leadbreath said:

i got a few original ones from ex-mod(ministry of defence) source, it will probbaly be ur best bet in the uk.

Click to expand...

Are you selling any?  As I too am interested.

leadbreath said:

i got a few original ones from ex-mod(ministry of defence) source, it will probbaly be ur best bet in the uk.

Click to expand...

Yes im interested in some Motorolla 2N3055's, pm'd you!

I've been using ON Semi 2N3055s in my BA283 projects.
They sound fantastic.

To me, it's not worth my time+$ to dig & dig for NOS Motorollas when there are current parts easily and cheaply available.

sorry guys i dont have any spare, i got mine from an surplus spares dealer in chatham, forget the name of the  place, he had shitloads. most of the stuff he sells is ex mod,he had some nice mod mullard tubes aswell.shit this guy even had some old turbine engines round back...crazy!!

Sh!t, sh!t, sh!t...flush it!