Rebranded transistors?
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From: langwadt on 18 Feb 2010 18:24 On 18 Feb., 16:30, John Larkin <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: > On Thu, 18 Feb 2010 14:52:25 GMT, Jan Panteltje > > > > <pNaonStpealm...(a)yahoo.com> wrote: > >I ordered some BC557 from Conrad.nl. > >Normally you can hardly red what is written on a transistor, > >but in this case the label is silver painted masked, > >and does not say 'BC557', but 'B557C': > >ftp://panteltje.com/pub/strange_transistors/BC557_rebranded_img_1806.jpg > > >Also it looks like the top has been grinded so as to remove any original marking. > >I scraped of some of the silver painted text, but I could find nothing under it. > >On one of these I thought I could make out the number '2' on the top, > >but then there are people whio see the strangest things in random patterns, > >so I am not sure: > >ftp://panteltje.com/pub/strange_transistors/BC557_top_img_1808.jpg > > >Any body has any idea what the difference is between a BC557 and a C557B? > >Or is it a BC557B? > >Or just any thing painted with the required number? > > >Other transistors (BC547) look totally normal from Conrad. > >I got a bit supicious when one of these did not work as expected, > >measured the beta, about 330 at low currents, but seems to drop to much lower at 100 mA. > > http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=222900688 > > John seem like a lot of trouble to go through to fake something that cost a few cents if you buy it from digikey -Lasse
From: Bitrex on 18 Feb 2010 19:45 John Larkin wrote: > On Thu, 18 Feb 2010 14:52:25 GMT, Jan Panteltje > <pNaonStpealmtje(a)yahoo.com> wrote: > >> I ordered some BC557 from Conrad.nl. >> Normally you can hardly red what is written on a transistor, >> but in this case the label is silver painted masked, >> and does not say 'BC557', but 'B557C': >> ftp://panteltje.com/pub/strange_transistors/BC557_rebranded_img_1806.jpg >> >> Also it looks like the top has been grinded so as to remove any original marking. >> I scraped of some of the silver painted text, but I could find nothing under it. >> On one of these I thought I could make out the number '2' on the top, >> but then there are people whio see the strangest things in random patterns, >> so I am not sure: >> ftp://panteltje.com/pub/strange_transistors/BC557_top_img_1808.jpg >> >> Any body has any idea what the difference is between a BC557 and a C557B? >> Or is it a BC557B? >> Or just any thing painted with the required number? >> >> Other transistors (BC547) look totally normal from Conrad. >> I got a bit supicious when one of these did not work as expected, >> measured the beta, about 330 at low currents, but seems to drop to much lower at 100 mA. > > http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=222900688 > > John > I've seen pictures of counterfeit capacitors that consist of the casing of say, a 200V 660uF capacitor, but inside is just empty space and a 160V 100uF capacitor mounted to the leads, like a Matryoshka doll.
From: Phil Allison on 18 Feb 2010 20:03 "Jan Panteltje" > > I ordered some BC557 from Conrad.nl. > Normally you can hardly red what is written on a transistor, > but in this case the label is silver painted masked, > and does not say 'BC557', but 'B557C': > ftp://panteltje.com/pub/strange_transistors/BC557_rebranded_img_1806.jpg ** It clearly says " C557B" The "C" very likely stands for Conrad. Makers will apply any number the buyer asks for. ..... Phil
From: Hammy on 18 Feb 2010 20:37 On Thu, 18 Feb 2010 19:45:43 -0500, Bitrex <bitrex(a)de.lete.earthlink.net> wrote: >> > >I've seen pictures of counterfeit capacitors that consist of the casing >of say, a 200V 660uF capacitor, but inside is just empty space and a >160V 100uF capacitor mounted to the leads, like a Matryoshka doll. Considering the time and effort spent I don't know how that could be very profitable. I guess if a major manufacturer did it they would make some coin or if you labour force worked for a nickel an hour in some sweat shop. Nothing really suprises me anymore.
From: Phil Allison on 18 Feb 2010 20:43
"Hammy" >>I've seen pictures of counterfeit capacitors that consist of the casing >>of say, a 200V 660uF capacitor, but inside is just empty space and a >>160V 100uF capacitor mounted to the leads, like a Matryoshka doll. > > Considering the time and effort spent I don't know how that could be > very profitable. ** Very simply. The shrink plastic label on the oversize can indicates a top brad name like Nippon Chemi-con or Sprague. What is inside is a small, no brand POS extracted from used equipment like old CFLs. Means converting worthless junk into cash using child labour in China or India. ..... Phil |