Author Topic: how  (Read 1329 times)

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Offline neo

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how
« on: July 14, 2016, 03:02:44 pm »
I take apart a lot of electronics for their parts, i can find datasheets for most of the complex ones. Though there are several components that border on just plain obscure, be it without anything or with nothing showing up the question is. How do i identify components if all conventional means fail or should i just give up on them.
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Online blueskull

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Re: how
« Reply #1 on: July 14, 2016, 03:39:40 pm »
If the top markings are not Google-able, then pretty much the only thing you can do it trying to trace out the circuit, and see if a standard FET/BJT/LDO fits in there. If not, then your reverse engineering work is f*ed.

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Offline jeroen79

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Re: how
« Reply #2 on: July 14, 2016, 04:35:56 pm »
Or try finding a schematic/servicemanual for the device you are taking apart.
It may contain a list of components.
 

Offline ZeTeX

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Re: how
« Reply #3 on: July 15, 2016, 08:14:25 am »
It happens.
Usually you would throw those component anyway.
Who would actually design something using one of those crappy components? You don't even know their specs.

Just don't bother too much, don't desolder them or use them, you will save a lot of headache.


 

Offline neo

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in reply
« Reply #4 on: July 15, 2016, 03:44:43 pm »
thank you, i am new to forums and secondly, blueskull thank you but that wouldn't work most of the time though it might so thanks for the idea, jeroen79 again good idea but next to impossible due to the intellectual property junk the companies do anymore and in closing,  ZeTeX i do for the entire reason that they are otherwise throwaway i don't have alot of cash lying around if i want something precise id buy new if i want to experiment i use junk.
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Offline Mosaic

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Re: how
« Reply #5 on: July 15, 2016, 04:53:32 pm »
Ok, try to get  old electronics from the pre 90's era with discrete parts (with markings) and schematics available online. A few old CRT TVs / PC monitors or test/audio gear that's defunct can also fill your junk box with a lot of useful parts. For CRT equipment, discharge all the caps etc. near the yoke with an insulated handle screwdriver or  similar.

For the semiconductor parts you'll need to to a bit of basic testing to ensure they're serviceable. Bipolar transistors, FETs rectifiers, maybe even some opamps from audio gear. Having a curve tracer is a nice gizmo for precisely profiling simpler semiconductors but that might be a stretch right now.

Search on Bangood.com for cheap combo component tester kits to handle FETs, bipolars, diodes, caps, resistors etc for < $20. They work passably well and quickly, I use a couple of them for identifying parts from 'grab bag' collections etc.

When I started out as a teenager I did a lot of scavenging like that. Get a good desoldering tool (Hakko?) though, those manual solder suckers are finicky and splatter solder. For ICs and such you'll need hot air desoldering or solder wick. Keep any hot air under 280°C to not damage parts.


 

Offline charlespax

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Re: how
« Reply #6 on: July 15, 2016, 06:46:49 pm »
When I first got into electronics I disassembled a bunch of stuff and sorted and organized a plenty of parts. I wouldn't call it a mistake since I learned a few things, but I can certainly say I wasted a bunch of time desoldering parts I would never use. You're probably be better off leaving the components on the boards. When you know what you need go hunting for it.

It feels good putting components into tiny labeled bags or boxes, but it's not worth your time.
 


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