Rampage owners - please help me ID this component!

smalltownguy2

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Pic attached. The sound board fried a component, and I can't seem to find any schematics that help me ID it.

Can anyone help me ID the component circled in red?
 

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Thanks, ELutz, that was enough info to zero in on it. There's only 2 axial lead tantalum caps on that board, and they're both 10mf. (CP14, and CP15)

I found a better scan of the manual here and was able to decipher that it is indeed CP14.

The schematics call it out as a "10 MF AX TANT" capacitor - so does this mean 10 millifarads? Or 10 microfarads?
 
Digikey shows me this for a 10μF axial lead tantalum cap. This should work, right?

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=718-1421-1-ND
This is the 10volt version - there's 20, 25, 35v versions too...


173D%20Series.jpg
 
Microfarads.

Also, I somehow doubt that really, absolutely needs to be a tantalum. You should be able to just solder a normal electrolytic in there.

-Ian

Good to know - I have several 10μf caps in my kit that I can pick from. That will at least get the board up and running until I can get the proper part from DigiKey later next week.

Here's to hoping I haven't fried the PIA chip on the board when the cap went up in smoke....
 
Here's to hoping I haven't fried the PIA chip on the board when the cap went up in smoke....

You didn't do anything wrong to cause the cap to go. Tantalums fail shorted and burn - that's just what they do. Electrolytics just dry out and leak or stop working - but tantalums like to burn. It's a common problem, especially in old computer equipment.

-Ian
 
Interesting excerpt I pulled from another forum discussing tantalum versus electrolytic caps.....


"In fact they don't tolerate voltage peeks and may explode if their ratings are exceeded. On the other hand, they are more precise, stable and suitable for higher frequencies. I've recently used tantalum capacitors after LDO regulators because of their low ESR."

I may just swap out ALL the tantalum caps on this board to 'lytics.

Any idea how I can determine the voltage rating? I don't see it referenced anywhere on the schematics parts list.
 
Any idea how I can determine the voltage rating? I don't see it referenced anywhere on the schematics parts list.

If you have a cap that hasn't failed yet, take it out of the circuit and connect it to a bench power supply. Simply increase the voltage until it explodes - then back it off a bit. :D

But, seriously, I'd say probably 16v, since that's what the normal electrolytics around it are. If you want to err on the side of caution, 25v. Of course, you could always use your meter to see what the voltage is in the circuit...

-Ian
 
Interesting excerpt I pulled from another forum discussing tantalum versus electrolytic caps.....

I may just swap out ALL the tantalum caps on this board to 'lytics.

No... don't do that without knowing exactly why they used tantalums to begin with.
These companies were notoriously 'cheap' - they don't just use expensive tantalums where cheap electrolytics would work for no reason at all.
-Something- caused that tantalum to go bad... they just don't spontaneously explode. Investigate that first.

Tantalums are wonderful in that they don't age like electrolytics. They have lower internal resistance than electrolytics. And they have have tighter tolerances.

Bad thing about Tantalums - they don't like reverse voltage at all. And, they don't take kindly to overvoltage.

I like to use them in areas such as timers, etc due to their tight tolerance and stability.

-- Ed
 
-Something- caused that tantalum to go bad... they just don't spontaneously explode. Investigate that first.

Tantalums are wonderful in that they don't age like electrolytics.

I'm going to have to disagree. Tantalums *do* age. And when they do, they fail shorted and explode. They age especially poorly with disuse. This is a very common problem in the vintage computer world - where boards have been sitting for decades, then plugged into a fully working machine, and *foom!*, the tantalum across the power rails on the card goes up in smoke.

Perhaps capacitors made in the late 80's/90's are better, but I see tantalums from the 70's and early 80's failing all the time.

-Ian
 
From what I've read, it appears that tantalums are also more susceptible to ESD and humidity risks than elecrolytic caps too.
 
I'm going to have to disagree. Tantalums *do* age. And when they do, they fail shorted and explode. They age especially poorly with disuse. This is a very common problem in the vintage computer world - where boards have been sitting for decades, then plugged into a fully working machine, and *foom!*, the tantalum across the power rails on the card goes up in smoke.

Perhaps capacitors made in the late 80's/90's are better, but I see tantalums from the 70's and early 80's failing all the time.

-Ian


I have never seen a tantalum fail due to aging and have been working on computers since before they became 'vintage' (I am often considered 'vintage'). OTHER components such as bulk electrolytics age and degrade beyond usable life - bulk caps on switching supplies going bad can easily cause voltages to go awry and can cause tantalums to fail. But, at this point, the tantalum is still not the source of the problem.
Yes, when they do fail, it isn't pretty. Still, every tantalum that I have seen that failed was caused by something other than the tantalum cap degrading.

Straight from the horses mouth (manufacturer):
"Tantalum capacitors do not exhibit aging."
 
From what I've read, it appears that tantalums are also more susceptible to ESD and humidity risks than elecrolytic caps too.

Aw come on guys. Have you guys actually ever designed either type of cap into a system? Ever had that system gone through full bore military shake and bake testing? Including prolonged temp extremes, humidity extremes as well as prolinged exteme shaking. I have. Tantalums - number of failures = zero. Electrolytics - number of failures = one (leads broke from shaking -- it was on the test equipment not on the equipment under test). Due to long life and temp extremes, I use exclusively tantalums on these boards - never in nearly 22 years that I have been making these boards has a tantalum ever failed.

Just reading random comments from posters on the internet does not constitute fact.
Neither tantalums or electrolytics suffer from ESD until you get to very small values...for both.
Humidity also has little affect on either cap type as well. They both tend to increase a tiny bit in high humidity. Low humidity tends to speed up drying out electrolytics over time.

Now, if we want to talk about temperature. Tantalums tend to survive high temps far better than electrolytics.

By far, the number one reason I have seen for failed or marginal electronic equipment - dried out electrolytic capacitors.
 
Due to long life and temp extremes, I use exclusively tantalums on these boards - never in nearly 22 years that I have been making these boards has a tantalum ever failed.

Argh!
I stand corrected. I did have one board with failed tantalums.
The user managed to feed 24VAC down the +12V rail.
Yes, the tantalums blew. And he also managed to crater half the IC's on the board as well.
 
While I am not going to argue PCB design.....I fix this stuff, but the design aspect is beyond my knowledge base. I generally trust the original designer's build. As Ed (G-P-E) stated.....you better know why the designer stuck a $1.50 tantalum cap in that circuit.....instead of using a $.05 cent electrolytic cap. Also.....I've been around long enough to know what Ed has done/does for a living......I would never argue PCB build/design with him!:D

Stick a 10µF25V tantalum cap in there and be done with it;)

Edward
 
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