i may ask the company i work for if i can email myself some of the pictures i have taken of counterfeit transistors side-by side with known originals for comparison. technically, the pictures are property of the company, so it is wise to ask first... there are actually 2 valid reasons i would not be able to post them publicly, the first being that the information they contain is proprietary, and publishing them may allow competitors to gain information they may not already have. the other reason is that since i started this blog, doing a search for "counterfeit transistors" brings this page up rather quickly. counterfeiters are always trying to "improve" their fakes, and anything in physical characteristics that they are not aware of continues to provide the original maker of the devices the "edge". once the counterfeiters see their mistakes, they will correct them, and make it more difficult to spot the fakes. the information i posted above is enough information to detect a very large majority of counterfeited devices. as with counterfeited money, the best way to spot a fake is to be well acquainted with the original, and distrust any parts outlet that has the parts at a large discount.. keep any known original output transistors when you replace them (even if they're shorted), as the carcasses are a good physical reference to make visual and dimensional comparisons with.


the company i work for has had counterfeit transistors show up from several different suppliers, and when i spot them i document everything immediately (pictures, Vbe and capacitance measurements, purchase orders, and detailed written information describing all of the characteristics that are anomalous). i don't deal directly with any parts vendors, so i want to make sure that the people who do are completely prepared with as accurate information as is humanly possible, and that they understand the information. it also helps if you can provide data sheets for the original parts. the vendor (if they're honest) may want to send their transistors out to be tested.

i do a lot of work, but rarely get pictures of it. i may ask the company i work for if i can get some pictures of the counterfeit transistors i have found (so i can post them here and at diyaudio.com). there has been a bit of activity in that area in the last couple of weeks, and my "database" of characteristics, both visual and electrical is growing rapidly.

find a computer equipment recycler that sells the dead equipment to metal scrappers. find out how much they get per pound (or kilo), and offer them double. they will usually be more than happy to sell you one, or 2, or 10.

Beautiful information! Thank you very much
Some pictures would be great, to make your blog even more friendly

Bad thing that people here tends to replace the batteries, instead of putting the whole unit into my claws

You sure know how to make a designer contented! Thanks a ton!

Mystery solved, thank you!!!

JPUGs were stopped after 3rd edition if I am correct-- all the best those ECL chips are obslete and mostly not available
why not use newer versions? ECL chips are known to draw higher current
if worked at high frequencies

Wow there are some retards working in the patent office; perhaps it only exists to make the government money?

ok, so a store sends a Samsung home theater receiver in to the shop. the model is one of a series of similar models, some models in the series have more features than others. there are 6 speaker jacks and a wireless card slot on the back of the unit. the 6 speaker jacks are marked "L-front, R-front, Center, Subwoofer, L-rear, R-rear", and they are color coded with various colors to match the colors of the speaker plugs. unit comes in with the complaint " rear channels not functioning properly". so the technician orders an amp board after verifying that the left rear channel is dead. the tech gets the new board, and installs it and tests the unit. same problem. so the tech calls me over to look at the unit, thinking they may have missed something. we do a reset, thinking some option may be set wrong. same problem. so i tell the tech to go into the setup menu and go to the speaker test page. so we start the speaker test, which steps through all of the speakers one at a time outputting white noise to each one. not only does the left rear channel not work at all, the right rear works only when the test signal is sent to the left front channel, as if the right rear and left front channels are wired together. so i take the original board since it was handy, and begin following the traces on the board back from the speaker jacks. the left rear channel traces go to what should be a pair of inductors (the amp outputs are bridged class D), but instead is unpopulated. same thing with the right trear except that there are two 0 ohm resistors (surface mount jumpers) tying the right rear channel connection to the left front. this obviously is some kind of mistake, unless Samsung was attempting "kluge surround" where the rear speakers are cross connected to the opposite front channel (L-F to R-R and R-F to L-R), but Samsung isn't THAT cheap, and even if that were so, forgot the jumpers for the left rear. so we looked at the schematic, and sure enough, the schematic was wired exactly the same way as what we traced out on the board. this is getting weirder by the minute. the tech calls Samsung tech support who tells the tech to return the amp board as DOB (defective out of box). i had a sudden thought, look in the owner's manual. so we look up in the owner's manual (which is written for not just the one model, but the whole series) and look up the speaker connections for this particular model. no speaker connections for the rear channels are plugged in to the amp, but the rear channels use a wireless card and wireless receiver. the setup for another model was on the previous page, and the rear speakers get plugged in to the amp on that model, and the schematic (which is also for the whole model series) shows that on that particular model, yes the inductors are there. so here we have a manufacturer cutting corners by not covering up the unused connectors, and not leaving them unmarked in the silkscreen for that model, and further confusing things by connecting one of the unused outputs to the output of a working channel, but it took looking at the user manual to find something that wan't mentioned in the service manual. seems that the store personnel should have RTFM as well.

I drawn a test circuit of 10124 IC which is tested as per the Test circuit given by them(Motorola).
But i didn't get any out put & IC also heated.
How can i get tested the IC with ECL outputs.

afterthought........
when i was a Calibration Tech in the Army, every calibration manual began with this instruction step:
STEP 1: Read the entire contents of this manual before continuing.

when it came time for our yearly inspection, everyone had to perform a calibration on a piece of equipment for the inspector. if the tech did not read the entire manual before even plugging in the equipment or gathering the required test equipment, they were FAILED on the spot.

3.1 is now out now.

It's a pretty major upgrade, lots of new features have been added.

Download it now.
OpenOffice.org - The Free and Open Productivity Suite

hello my friend

i have a project to coplete and a have some problem, do you have anything in my following question?
Each ALU in a component includes special circuitry for performing
> the shifting operation, i.e., make a binary number shifted by a
> specific number of bits. An example of a shifting operation is this:
>
> Q: Getting the binary number 100010001101 shift it right by 3 places
> A: The result will be 000100010001.
>
> You are asked to design (both in layout and schematic) a shifter
> circuit
> (combinational) that performs both left and right shift in a 16-bit
> number.
> The maximum shifting amount is 8 bits and all shifted out bits are
> discarded.
> The shifted in bits should be feeded by an external input.
if you have anything i will appreciate.

I have built a very similar circuit for producing long electric arcs. Rather than a relay, I simply used a power transistor to pulse the ignition coil. I run it at a few khz to get a nice relaible arc. I've also seen projects that connect the coils in series for higher output voltage. I'm thinking about trying that for rev.2.

No. ??? . I don't understand, my english no good.

Hurricane control. phfft. Why not just tether one and use it for your own evil intentions (or maybe generate a city's power with it). See
Creating Tornadoes to Power Cities? | EcoGeek - Clean Technology
and Man-made 'tethered tornadoes' touted as a viable power source

I suggest you ignore the comment about the trial 1-metre-high self-sustaining hurricane producing excess energy... although it would be handy to have a little hurricane under the house producing power for the rest of the street. Or a cyclone-powered car

its always good to put a face to the posts

well said Mike! after all this movlw etc can be done later also.
but a foundation in digital fundamentals makes a person fit for his life time.

I would think an electric fence spends most of its time producing a voltage with nothing to shock.
Since this has a relay anyway, could it be made to operate only if a detectable leak to ground appears ?
Maybe a circuit could be made using the fence as a detector, then the relay could switch over to electrify the fence, if the fence sensed a leak to ground.
Then back again after a short period.
This would extend battery life considerably.

i think there are 2 sources of the line harmonics phobia. the first is from the audio "golden eardrum" society. anything except "pure AC" is unacceptable to power audiophile equipment. so somebody drums up this fear of the deleterious effects of line harmonics. then thy turn around and offer to sell you the latest (and obviously MOST expensive) AC line conditioner and "cryogenically de-stressed" power cords.

the second source is actually a legitimate concern is from the ham radio community. RF noise from power lines can be quite annoying if you are trying to grab a signal from the noise floor but all you can hear is BZZZZZZZZZZZZZZZZZZZZ.