might just being paranoid, but i blew some of my output transistors and got a new set from www.futurlec.com
the old ones are motorola MJL21194 and the new ones are ONsemi ones
(i know onsemi took over motorola semis or something?)
problem is that they look different in a few ways:
the legs taper differently, the legs have stalks, the top of the rear metal has an indent (kinda)
below is the pic from Rod's site http://sound.westhost.com/counterfeit.htm
and attached is a pic of my new ones
i seached here and no one has reported fake MJL's (maybe too cheap to fake?) but i just thought i would ask???
the old ones are motorola MJL21194 and the new ones are ONsemi ones
(i know onsemi took over motorola semis or something?)
problem is that they look different in a few ways:
the legs taper differently, the legs have stalks, the top of the rear metal has an indent (kinda)
below is the pic from Rod's site http://sound.westhost.com/counterfeit.htm
An externally hosted image should be here but it was not working when we last tested it.
and attached is a pic of my new ones
i seached here and no one has reported fake MJL's (maybe too cheap to fake?) but i just thought i would ask???
Attachments
They dont look anything like the samples I recieved directly from OnSemi fairly recently... so beware.
I got these from Avnet -- MJL21194 -- f you order from On-Semi's webstore the orders are filled by Avnet (but Avnet is not the lowest priced vendor) -- and you usually have to order a few hundred from them :
An externally hosted image should be here but it was not working when we last tested it.
Yes, i follow jaycee, i also got some samples recently, the look like
the pictures from Rod and jackinnj !
It's very sure you don't have onsemi-devices, but does not mean
they are bad...
Did you really pay 2,90$ ? Futurelec don't sell them as onsemi, so
you can't pee at their legs... Onsemi lists them for 2,90$, can't
imagaine that any reseller sells them at this price...
Mike
the pictures from Rod and jackinnj !
It's very sure you don't have onsemi-devices, but does not mean
they are bad...
Did you really pay 2,90$ ? Futurelec don't sell them as onsemi, so
you can't pee at their legs... Onsemi lists them for 2,90$, can't
imagaine that any reseller sells them at this price...
Mike
Well, they don't sell them as On, but they sell non-On devices marked as On. Just as bad in my book.
On a related note, I see the B&D Enterprises is trying to provide a fake transistor eveluation program. Last I checked only one device tested so far. http://www.bdent.com/nesda.jsp
On a related note, I see the B&D Enterprises is trying to provide a fake transistor eveluation program. Last I checked only one device tested so far. http://www.bdent.com/nesda.jsp
those pictures tells who they are!
I got originals too but does not look like on the attached.
so beware.
yes, i paid $2.90us = $3.80aud (compared to $11.95aud at Jaycar)
i saw various other sites advertising them at $3.50 and $3.80 etc and i thought that $2.90 was just the cheapest of them all...
well, thanks for confirming my suspicion.
but as one poster said - they may not be true on-semi's but they might do the same job?
i will contact futurlec and confirm that this is the case, then i will install them and run them and if they blow - i have a 90 day guarentte...
(it is lucky i only blew one channels, i have a working set of Motorola's in the other side for direct comparison of output performance 😉 )
i saw various other sites advertising them at $3.50 and $3.80 etc and i thought that $2.90 was just the cheapest of them all...
well, thanks for confirming my suspicion.
but as one poster said - they may not be true on-semi's but they might do the same job?
i will contact futurlec and confirm that this is the case, then i will install them and run them and if they blow - i have a 90 day guarentte...
(it is lucky i only blew one channels, i have a working set of Motorola's in the other side for direct comparison of output performance 😉 )
If you have a diode test function on your DMM you could compare the pin readings to the known good ones. That would give you at least some idea. Be careful not to blow any other devices when they fakes blow... 😉
Fakes
These are the same as some fakes I recently returned, purchased from an australian wholesaler/retailer. They were motorola labelled (M in circle), date code CX002 something meaning 2000. I sent images very similar to yours to ON-Semi tech advice and got a reply indicating that the Motorola had got out of semi manufacture in '98 so they could not possibly have been theirs. Also, the packaging was not theirs. I also noticed that the mounting was not flat (hold two together by the bolt holes and there's a good 1/2mm gap. Mine were 21193's but apparently the 21194's were also similar packaged and definately counterfeit.
If yours are on-semi labelled maybe they have got a little cleverer but the packaging is the same (legs taper to the middle of the package not the middle of each leg, bumps in the plastic where each leg comes out, slightly thinner) and does not match the ON-semi or motorola datasheet package design, so they are definately counterfeit parts.
Return them to the supplier and inform them of what you have found. PM me if you would like photos of the ones I have returned.
These are the same as some fakes I recently returned, purchased from an australian wholesaler/retailer. They were motorola labelled (M in circle), date code CX002 something meaning 2000. I sent images very similar to yours to ON-Semi tech advice and got a reply indicating that the Motorola had got out of semi manufacture in '98 so they could not possibly have been theirs. Also, the packaging was not theirs. I also noticed that the mounting was not flat (hold two together by the bolt holes and there's a good 1/2mm gap. Mine were 21193's but apparently the 21194's were also similar packaged and definately counterfeit.
If yours are on-semi labelled maybe they have got a little cleverer but the packaging is the same (legs taper to the middle of the package not the middle of each leg, bumps in the plastic where each leg comes out, slightly thinner) and does not match the ON-semi or motorola datasheet package design, so they are definately counterfeit parts.
Return them to the supplier and inform them of what you have found. PM me if you would like photos of the ones I have returned.
Further to my previous post, the issue is not to do with whether fakes will do the same job as the authentic devices, although most won't (almost all of the counterfeit devices fail at much lower loads/voltages than the real devices and the MJL21194 fakes that are the target of this thread are not flat on their mounting surface so may overheat) but that the manufacturer of the counterfeit devices are unlawfully making use of the trademark of another manufacturer. This unfairly tarnishes the reputation of the authentic manufacturer and that of other entities down the line (wholesalers, OEM's) and can leave the end purchaser (you and I) with substandard devices that are not able to be trusted. This is not acceptable.
If an alternate manufacturer comes to an agreement with (for example) ON-Semi to second-source a device and uses their own trademark (as mospec obviously has done with the MJL15003/004 TO-3 devices), this is a totally different situation. Here the customer (you and me) are being provided with a clearly different device with similar but seperately specified characteristics and no deception is taking place.
If an alternate manufacturer comes to an agreement with (for example) ON-Semi to second-source a device and uses their own trademark (as mospec obviously has done with the MJL15003/004 TO-3 devices), this is a totally different situation. Here the customer (you and me) are being provided with a clearly different device with similar but seperately specified characteristics and no deception is taking place.
tinkerbell:
To my knowledge, your devices are very likely to be fakes. I remember seeing pictures of similar devices with similar cases and markings being reported as fakes, while On-Semi uses different case and letter styles.
Could you open one device and show us the die and internal layout?
To my knowledge, your devices are very likely to be fakes. I remember seeing pictures of similar devices with similar cases and markings being reported as fakes, while On-Semi uses different case and letter styles.
Could you open one device and show us the die and internal layout?
There are a whole lot of fakes especially in the ON/Motorola MJXXXX
series. i have been caught with MJ15003 via Dick Smith here in Aus/NZ
On opening the TO3 lid; the die was a tiny bit of silicon and nowhere near the rated power of the original device. What's more the vendors of these fakes will replace the semi, but not the time and cost of other components blown up in the process. Comparing transistors with the originals is one way of checking, via the text on the device and the topography of the heatsink area.
Also worth noting is that semi buyers will buy on best price and max profit and often don't check if the product is an original. If the transistor looks cheap, then it's likely a fake. Buying from a supplier you trust and paying a few dollars extra, is better than looking at your amp and wondering what mistakes you have made to cause the blow-up when all along you bought faulty components. If you are in doubt, then setup a simple current dump on the transistor and see if it matches the spec rating.
It just **** me off that fakes have become so widespread.
series. i have been caught with MJ15003 via Dick Smith here in Aus/NZ
On opening the TO3 lid; the die was a tiny bit of silicon and nowhere near the rated power of the original device. What's more the vendors of these fakes will replace the semi, but not the time and cost of other components blown up in the process. Comparing transistors with the originals is one way of checking, via the text on the device and the topography of the heatsink area.
Also worth noting is that semi buyers will buy on best price and max profit and often don't check if the product is an original. If the transistor looks cheap, then it's likely a fake. Buying from a supplier you trust and paying a few dollars extra, is better than looking at your amp and wondering what mistakes you have made to cause the blow-up when all along you bought faulty components. If you are in doubt, then setup a simple current dump on the transistor and see if it matches the spec rating.
It just **** me off that fakes have become so widespread.
Limiting liability to only the component is not going to stand up if they are fakes. In most juridictions this is forgery or cheating.
Buying from expensive sources is not necessarily the key for success, I've stumbled into a lot of expensive fakes (at least here in Spain). Most sources here just don't seem to care at all about what they sell, they may have fakes this week, and original devices the next week... You may even get a random mix of genuine parts and several kinds of fakes when you buy in quantity, they handle semiconductors like potatoes.
If you order direct from Onsemi, you won't get fakes.
I've tested my MJL 21195/96 and MJL 4281/4302 and it takes a good amount of current before the transistor even starts to heat, kind of like a TO3, heh.
It really sucks that people make fake transistors to make a dirty dollar.
Regarding the transistor checker that uses the light bulb and the bridge rectifier..........Do you have to heatsink the transistor under test, or do you just hit it with power for a real short period of time?
I've tested my MJL 21195/96 and MJL 4281/4302 and it takes a good amount of current before the transistor even starts to heat, kind of like a TO3, heh.
It really sucks that people make fake transistors to make a dirty dollar.
Regarding the transistor checker that uses the light bulb and the bridge rectifier..........Do you have to heatsink the transistor under test, or do you just hit it with power for a real short period of time?
Just to note, I was not referring to Farnell. I have only purchased fakes from small (mostly EBay-type) dealers.
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