THREE? Gee, why don't you put a capacitor in series? Or look at the output with a 20 Ohm resistor? Or put an expendable speaker from an old TV etc in series to it.
I texted the seller and they sent me these pictures, the IC looks better than the ones they have on their shop and I think they look identical to the original... what do you guys think?
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I actually noticed this too but their actual product looks nothing like this picture, see my previous post
I think they are not lm3886, the writing looks funny , it might be National/TI part, but not lm3886.
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I built up my first LM3886 amp a good few years ago.
The thing wouldn't work.
It was a reputable source so should have been good.
I had volts on output when it should be zero volts.
I then spotted the mistake.
The long pins were shorting on the pcb pads of the back pins.
So the next one I soldered in I left it a little proud of the pcb and it worked fine.
The thing wouldn't work.
It was a reputable source so should have been good.
I had volts on output when it should be zero volts.
I then spotted the mistake.
The long pins were shorting on the pcb pads of the back pins.
So the next one I soldered in I left it a little proud of the pcb and it worked fine.
The one on the left at least is Laser engraved and *looks* professionally made, the one at right has TERRIBLE silkscreening, I can print much better on my kitchen table with one hand tied to my back.
Even worse: fully enlarging the image I can see the *thin* sharp outline of each letter, surrounded by a flood of white ink.
As a silkscreener: they had a well made original artwork, proper line thickness, etc, then inexperienced/cheap/in a hurry operator had a problem with ink drying up and clogging screen pores (a very common problem) so he added ink solvent ... way too much of it, so too liquid ink spreads too much around.
If silkscreening is that sloppy, imagine what they fit inside 😎
Most probably you can wipe that white ink out with a ball of cotton wetted in acetone.
We can´t add anything new to what is already written, just take the plunge and buy the U$13 one, I suggested a somewhat safe way to test it.
OR:
Pllan B: ditch the LM3886 idea and build a conventional discrete 50/60W amp.
It´s easier to find real discrete parts and if they fail they can be repaired.
I use TIP142/147 since about 2006 because of that, not expensive or unavailable enough to attract fakers.
Unless you buy 10 for 1.25 US$ from some ignote seller in China, but then you love playing Russian Roulette 😛
JMFahey
Those 2 chips are 100% authentic . I just posted those pictures there so he could compare them with his chips. Sorry for. The confusion .
Those 2 chips are 100% authentic . I just posted those pictures there so he could compare them with his chips. Sorry for. The confusion .
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Thanks.
May be authentic, still stand by my very poor silkscreening comments 🙂
Since everybody and his brother went to laser engraving years ago, only way I would expect a silkscreened part from a major manufacturer is from very very old NOS.
Out of curiosity just checked a few old parts drawers: silkscreened ones showed dates from ´74 to ´97, one had a single digit code starting with 7 , might be ´97 or even 2007, all others were laser burnt.
May be authentic, still stand by my very poor silkscreening comments 🙂
Since everybody and his brother went to laser engraving years ago, only way I would expect a silkscreened part from a major manufacturer is from very very old NOS.
Out of curiosity just checked a few old parts drawers: silkscreened ones showed dates from ´74 to ´97, one had a single digit code starting with 7 , might be ´97 or even 2007, all others were laser burnt.
What?! 😱 No offence but those two lm3886 looks 100% authentic. Anyway i understand your point. Yes NOS chip.
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I would be very skeptical that there IS any NOS 3886 or TDA2050 left on the planet. The last of the original runs would be long gone and only recent manufacture 3886 would be available at all. If you’re looking for TDA2003 (and sometimes even 2030) you can still find them because nobody uses them anymore, and predecessors of the 3886 seem to be more available. NOS on all the predecessor types may still be around after the 3886 evaporates entirely.
If they do decide to EOL them it will be a mess - like the mad scramble to get the last 2N6609’s and Sanken MT200’s were. Maybe not enough industry demand anymore, but a lot of angry users left holding the bag.
If they do decide to EOL them it will be a mess - like the mad scramble to get the last 2N6609’s and Sanken MT200’s were. Maybe not enough industry demand anymore, but a lot of angry users left holding the bag.
You are right about the silkscreen , but that how they chips were marked back then .
Here are 2 picture with lm3886, lm3875 and lm4702 , same era , 100% authentic.
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Try finding a 1988 TDA2050 for sale *today*. I suspect you got those some time ago.
Thanks everyone for your help, Ive decided to buy the LM3886 from this seller and just hope for the best. I initially asked because the IC in their pictures looked suspicious but now I know that the pictures are taken online and their actual units look more decent i'll take the risk.
The vendor named in the photo attached to post #1 (JK_Parts, in green in the photo) is not from Venezuela. They are from China.
I don't recommend buying those parts.
I don't recommend buying those parts.
I can try to arrange some NOS LM3886T if you want to.
YES, still available here but not sure about quantity. Insulated package is more popular here than non-insulated 'T' version for ease of use & maybe that's the reason no one wants to buy those 3886T despite technical superiority.