tantalum capacitors

[Frankenstyne]

Here is a couple pics of the depopulated items I am not sure I am going to do with yet. If any of these are what you are looking for you are more then welcome to them.

Cheers,
Freak

 

[Buzz]

Anyone know if these components have any PM values inside them please?

I have several thousand unused ones and not sure what to do with them.
The only identifying mark on them is b rx375 7208t

Thanks for any help

 

[etack]

Frankenstyne thanks for your interest in you pic the ones I would be interested in are circled in red.

The majority of the others are junk AL caps can style or poly with Al film

look at my post and it shows what I'm looking for don't throw them out I will buy them.

Eric

 

[Frankenstyne]

I will gather up what i have and set them off to the side with a sign "For etack" .

 

[Geo]

so according to this diagram, if its a Ta capacitor of this type, the case is silver?



ok. so i incinerate the suspect Ta capacitors in a closed container to contain the exploding caps. then a warm bath in hcl will weed out the aluminum from the Ta caps. another incineration and a bath in dilute nitric acid 50/50 will remove the silver or should i use nitric first?

 

[jimdoc]

You should be able to tell the tantalum capacitors by their weight.

Jim

 

[butcher]

Geo those were fairly old capacitors, most had a red color band on one end, I used to hate circuit boards whith these capacitors as the caps would usually go bad.

I have some of these old capacitors but have not tried to process them.

Before incinerating I would cut capacitor open with diagonal plyers, just so it would not explode.

If you did not have too many it may be better to seperate silver shell mechanically.

After inceneration metal shells could also be seperated mechanically.

I am unsure what metals the solder seal contains, you could cut up a cap and test the solder seperately.
just to see if tin is involved in the solder, which if doing these in HNO3, may give problems.

I do not believe they contain aluminum, and see no need for HCl, at this point.

I would also probably try cutting off the wires and cuttining open a few of these capacitors and melt to see how that would work.

 

[etack]

so according to this diagram, if its a Ta capacitor of this type, the case is silver?

Most are not going to be silver. Use silver testing solution.

If you have a lot first put them in HCl to weed out AI caps them heat to drive off HCl then put in nitric to remove Ag. Whats left is Ta it doesn't react with Nitric or HCl I'm not sure about them together.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=2919&hilit=Tantalum+silver&start=20

This thread shows what the silver ones look like.


Eric

 

[Geo]

Eric, i had the great fortune of processing a few tons of old military test equipment and this stuff is full of those types of caps. i toss nothing so i still have all the components after these last couple of years. i have rotary switches the are 6-8 inches long with those types of caps soldered all over them. i need to go through this stuff and break some of it down. it still contains a fair amount of gold bearing stuff too. ive been dealing with other peoples stuff so long, mine has been sitting on the back burner. i have well over a ton of computer mother boards that need to be depopulated.

 

[butcher]

you may be able to sell the rotary switch's with those capacitors (or resistors soldererd to the rotory switch) to make decade boxes.

http://www.ebay.com/sch/i.html?_nkw=+capacitance+decade+box&_sacat=0&_odkw=resistor+capacitance+decade+box&_osacat=0
http://www.ebay.com/sch/i.html?_nkw=decade+resistance+box

decade boxes are used in repair of electronics to select a capacitor, and substitute it in the circuit.

 

[Geo]

thanks Butcher, ill check that out. if i have half of what i had intact, it may turn out to be worth alot more than scrap. dont worry Eric, i have plenty that was bent and stuff thrown on it. ill get out tomorrow and go through some crates and barrels just to see what i can scare up.

 

[etack]

Don't worry about me you make your money first then make mine for me. :lol:


Eric

 

[macfixer01]

Hey,

GSP stated in a post he believed the red plugged ones were running 40% ag.

-Andrew

I don't know, I never have believed that these red striped caps are tantalum. They're very light-weight whereas I've always found the tantalum caps to be quite heavy for their size. They also fail the crush test someone else proposed here recently. I had a few sitting around here and they crush quite easily just like electrolytic capacitors.

macfixer01

 

[Geo]

Eric, here are some examples of the canister types i have found on the one piece of equipment i went out and picked up to look at. there are other suspect parts but these im fairly certain of. the yellow ones in the middle are from left to right undamaged, with yellow plastic off, with red epoxy off (looks like a silver case), fully open, extracted pellet. the top two center are Ta cases. the bottom right is silver case. the others im sure are Ta but unsure of the case.

 

[Geo]

this is another array of Ta caps from another 1 piece of equipment. actually, its just 1 board. i have piles of this stuff. ill gather up a nice shipment to you and we'll work out a percentage on the silver. i will have plenty to play with myself. i really could use a little extra cash for the holidays. 8) those things are very not easy to open.

 

[AndyWilliams]

this is another array of Ta caps from another 1 piece of equipment. actually, its just 1 board. i have piles of this stuff. ill gather up a nice shipment to you and we'll work out a percentage on the silver. i will have plenty to play with myself. i really could use a little extra cash for the holidays. 8) those things are very not easy to open.

View attachment 2

View attachment 1

Hey guys, don't want to barge in on the dance, but I'd like to buy one. Just to play with of course, and heck, I'm still iffy on these things anyway! Just quote me a price plus shipping.

 

[etack]

Geo If you take thees apart look at the two red circles. can you open that green thing I was reading an old book on Ta caps and in it was some pics of some like that. Look to see first if its a battery and secondly which side the polarized marking is on. Ta caps are marked on the (+) side as Al caps are on the (-) side and I think batteries are marked on both.

The other circle Lou had made a remark a few years ago to the effect that some of the old antenna plugs were made of solid silver on old military test and radio equipment. Always worth the check.

You don't need to be gentle on them in the end its all scrap metal. :lol: the leads are most likely nickel so you will be able to gather them up with a magnet.

 

[Geo]

will do.

 

[nivrnb]

this is another array of Ta caps from another 1 piece of equipment. actually, its just 1 board. i have piles of this stuff. ill gather up a nice shipment to you and we'll work out a percentage on the silver. i will have plenty to play with myself. i really could use a little extra cash for the holidays. 8) those things are very not easy to open.

View attachment 2

Geo,

The Ta caps in the photo, I found it easy to place one in front of a heat gun, the solder on the inside will melt and they pull apart very easy.

Rob

 

[Geo]

Rob, that is great to know. ill try that shortly. the ones in the yellow plastic has a silver case. i tested with silver testing solution every single one i can find. this has turned me on to a part of this stuff i thought was worthless. i consider the units in the picture as a kind of blade. there was banks of them in several big pieces and they slide in and plug in with the blue connector. there may be up to 50 or 60 of them if i can find them all. ill be busy for a little while. as you can see, i still havent removed the gold plated connectors off of them yet. i have alot of that kind of stuff to go through.

i keep saying i have tons of crap to deal with. :lol: i still get between 50 and 100 computers a month piling up on top of all that.

hey guys, i have some wonderful news. i went to my pulmonologist today for my 6 month checkup. the doctor was very pleased after my test came in and told me my lung function had improved. my last visit, it was at 36% and he was talking about a lung transplant. today it had improved to 52% and he said that the transplant wasnt even an option with it that good. he said that what ever i was doing, to keep it up. i didnt tell him what my hobby was. :shock: i have taken measures to improve my exposure to harmful vapors including fume control and better work practices. its showing in my improved health. im so happy, i just had to tell everyone.