Low vs High Grade Circuit Boards?

[DJWhiteGuy]

Hello, I have been dismantling things for the last several days and have accumulated many circuit boards. I was wondering how to determine if the board is low or high grade?

I have been told look at the resistors - the smaller the better. Also, to look for gold-colored pathways.

I was recently told about the "see-through test" and was wondering how reliable it is. That is, holding the board up to a light source. If you can see through it, its low grade. If you do not see the light / BARELY any light, it is high grade. This all relying on the thickness of the board as a indicator.



Your thoughts? I plan to take everything back today and am hoping to maximize on them instead of throwing them all off as breakage.

Thanks for your time guys!

[ryanw]

This thread is very helpful for sorting your boards.

http://www.scrapmetalforum.com/elect...rds-parts.html

[DJWhiteGuy]

Thanks for the link, the pictures really help! Any idea if the "light test" I talked about is accurate?

[ryanw]

I don't know how accurate that is..never tried it myself. Here are some general characteristics of low grade boards:

Usually brown or tan on at least on side. <-- Best/easiest way to sort while you're learning.
Normally easily breakable.
Have large capacitors, resistors, aluminum heatsinks, transformers, and other material that isn't worth all that much per pound.
Very few, if any IC chips.

Once you get these out of the way, then you should have mostly valuable boards left.

Without going into much detail (you'll have to look up what these look like) here are the most valuable components of many circuit boards:

Gold plated pins, and connectors.
IC Chips
BGA's (Ball Grid Array) chips and Flatpacks
Visible gold plating on boards(Most of the time, gold plating doesn't continue under the solder mask, but it can)
PROMS
EPROMS - These have cool looking windows on the tops of them usually under a sticker.
It's late, and I can't think of anything else! There are other components that can be valuable too, but these are the ones to focus on for now.

Anyway, more of the above items give the board more value. Lesser value components decrease a board's value. The board itself has no value at all. It just holds together everything that does.

[Mechanic688]

For now till you've done more reading, do not pull components off of the computer related boards, just brown boards.
If you pull parts off of computer related boards then you will be downgrading the value of them.
You will find posts here of what can/cannot be removed.

[DJWhiteGuy]

I don't know how accurate that is..never tried it myself. Here are some general characteristics of low grade boards:

Usually brown or tan on at least on side. <-- Best/easiest way to sort while you're learning.
Normally easily breakable.
Have large capacitors, resistors, aluminum heatsinks, transformers, and other material that isn't worth all that much per pound.
Very few, if any IC chips.

Once you get these out of the way, then you should have mostly valuable boards left.

Without going into much detail (you'll have to look up what these look like) here are the most valuable components of many circuit boards:

Gold plated pins, and connectors.
IC Chips
BGA's (Ball Grid Array) chips and Flatpacks
Visible gold plating on boards(Most of the time, gold plating doesn't continue under the solder mask, but it can)
PROMS
EPROMS - These have cool looking windows on the tops of them usually under a sticker.
It's late, and I can't think of anything else! There are other components that can be valuable too, but these are the ones to focus on for now.

Anyway, more of the above items give the board more value. Lesser value components decrease a board's value. The board itself has no value at all. It just holds together everything that does.

So pretty much, if its green odds are it is mid or high grade?

If anyone has a few boards of both grades laying around, take a moment and hold them each up to a light. I think it makes sense... high grade is too thick for light, where low grade is easier to see through.

Anyone able to confirm this as a reliable method?

[happyscraper]

DO NOT USE THAT LIGHT TEST!!!! There are very few boards that light will shine through. Like stated above any board that is brown on one side will be low grade. The link that Ryanw posted is the best way to start to learn. Grading boards is the hardest part of scrapping electronics. If at all possibale try to find a local buyer by you, that way they can work with you on gradding the boards the way they want them. Every buyer seems to have a diffrant grading system. Also when Ryanw talked about boards being green they are green all the way through, very few that are green on both sides and brown in the middle will be mid grade but thiere are all ways exeptions. One more thing, just because there is gold on the board dose not make it a mid to high grade board.