smd's

[Barren Realms 007]

thank you Oz.

by now i have processed 250 grams of mixed monocap's from cards, CPU's, mother boards, just about everything that looks like a monolithic capacitor, from a relatively new scrap (no more then 15 years old).

and the yield is steady - 0.5% Pd from total mass.

Is that .5% of the weight of the capacitors only?

 

[samuel-a]

yup

 

[lazersteve]

thank you Oz.

by now i have processed 250 grams of mixed monocap's from cards, CPU's, mother boards, just about everything that looks like a monolithic capacitor, from a relatively new scrap (no more then 15 years old).

and the yield is steady - 0.5% Pd from total mass.

Sam,

Mixing the various SMD components may be skewing your results downward. I've processed reels of all the same type of capacitors several times and have had yields upwards of 2.5% of the total component mass.

As an experiment you should gather up the monolithics only off the slotted PII and PIII cpu cards. Carefully weigh and process these components without mixing in any other SMD devices or monolithics from other sources.

Steve

 

[samuel-a]

yes, i'm awar that the mixing it the cause of the downward in yield i'v expirienced.

i had a seller with 220 lb of reels, stright from the factory, and tested positive for Pd, but he backed down....


About the white powder, well, from 250 of monocap's thers about 220 grams of it.
no change with bright lite... no reaction to nitric/HCL-Cl/AR.... what the hack is that :?:
how can i proof it's cordierite or not?

 

[JustinNH]

I'm with ya Sam. I dont have access to enough of a certain type so I put all into a container to process. I will spot check some if there are a lot on a certain board and test with DMG... but otherwise they all go in. I have a solution at my parents house I still need to finish with. Had to leave it there when I got an apartment, but I am closing on a house in a month and should be able to finsih it up :mrgreen:

 

[Anonymous]

Hi Justin,
Hows the snow up your way?
I cant wait to get out prospecting this year, I have made some hand pump sluices for my kids and I am building a 3 inch dredge.

Jim

 

[JustinNH]

Hi Justin,
Hows the snow up your way?
I cant wait to get out prospecting this year, I have made some hand pump sluices for my kids and I am building a 3 inch dredge.

Jim

Hey Jim

It is coming down pretty good... but its 35 out and its a wet snow. I think it is going to change over to rain soon and hopefully cancel out the snow we did get.

Yeah, I know what you mean. My buddy and I drove up to the gold panning spot to check it out. There is about a solid foot of ice over most of the river. Good thing its a fast river and once it melts the ice will start to go fast.

Building a dredge? That should be cool! I made a sluice box when I first started but didnt try making the dredge

 

[pesco]

Very interesting topic.

As I wasn't around when it was started I'd like to add few corrections to identification of the elements:

2 - inductors, could also be capacitor, PTC, NTC (termistors), PRG, PRF, contents -> Pt, Pd, Ag, Ti, Ni, Sn,
5 - most likely LC or RF filters, could also be antenna, chock coil, you see this elements mostly in radios/mobiles, contents -> not a clue :mrgreen:
5 - most resistors, could also be NTC, PTC, fuse, contents -> Pt, Pd, Ag, Ti, Ni, Sn

Where I listed "contents" it doesn't mean that every single component will contain all of the elements, but it means that every MIXED batch of the same type of components manufactured by different manufacturers and in different times will contain all the elements listed :mrgreen:

Wide range of possible types of components comes from a simple fact that many are visually indistinguishable and there are only 2 certain ways to find out what the component is :
- having a schematic of disassembled board or having unused components with markings on the reel
- testing each of them -> for masochists only, its like checking every single grain of sugar if it really is sugar before you put it in your tea :mrgreen:

 

[samuel-a]

Where I listed "contents" it doesn't mean that every single component will contain all of the elements, but it means that every MIXED batch of the same type of components manufactured by different manufacturers and in different times will contain all the elements listed

Wide range of possible types of components comes from a simple fact that many are visually indistinguishable and there are only 2 certain ways to find out what the component is :
- having a schematic of disassembled board or having unused components with markings on the reel
- testing each of them -> for masochists only, its like checking every single grain of sugar if it really is sugar before you put it in your tea

You have said it as best as anyone could.

Thank you for the addition.

Iv'e recently sampled MLCC's, hopefully in a few days i could share the results.

 

[pesco]

I forgot to include Au above - you might find traces of it in resistors.

 

[lazersteve]

It's easy enough to test common boards types for precious metal bearing surface mounted devices (SMDs) and keep a notebook of the board makes that have the good parts on them.

For example you can test the various smd's from slotted style cpus and determine which parts contain the pms on them. All similar make and model boards should have the same smds used in their manufacture. The key to finding the smds with pms is to find those smds manufactured in the same year, by the same manufacturer, for the same purpose.

As I've stated numerous times: proper sorting of your escrap leads to more accurate yield data and repeatable results.

Steve