Classic Bead Tantalum Capacitor Failure

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AnalogJoe
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Re: Classic Bead Tantalum Capacitor Failure

Post by AnalogJoe »

I find todays electrolytics to be very impressive, for example, take a look at Panasonic FR series of capacitors, they are very low impedance and are rated 5000 to 10000 hrs at 105 °C, those caps will last a long time. Some electrolytics are crap thou, my LG Plasma TV refuses to turn on the first 2 or 3 times I hit the On button, it tries to turn on but a relay kicks in and it turns off again, it does have a stand-by voltage and once its On there is no other problem, I haven't opened it yet ( I'm waiting till it doesn't turn on at all!) It could be something else but I am pretty sure it is capacitor fatigue, and that problem only seems to get worse with time, I refuse to buy a new TV, I love the picture of plasma screens, they are a bit power-hungry thou.
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mediatechnology
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Re: Classic Bead Tantalum Capacitor Failure

Post by mediatechnology »

AnalogJoe wrote: Fri May 29, 2020 11:51 am Old thread, but I also had the same problem with a Tektronix pulse generator, the tantalum bypass caps kept blowing up, I replaced them with Panasonic aluminum electrolytics and problem solved. I dont know why would anyone use Tantalum in audio equipment, I cringed when I saw a pair of 47uF Tantalums back to back in a NP configuration straight on the output of the Line input differential amp on each channel of my MCI console, they had to go. Everytime I see the distortion curves of tantalum caps I go :o
I have a THD plot of tantalum capacitors I did for the late Bob Pease that I should find and post.
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AnalogJoe
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Re: Classic Bead Tantalum Capacitor Failure

Post by AnalogJoe »

mediatechnology wrote: Tue Jun 02, 2020 7:39 am
I have a THD plot of tantalum capacitors I did for the late Bob Pease that I should find and post.

That would be great !
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mediatechnology
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Re: Classic Bead Tantalum Capacitor Failure

Post by mediatechnology »

Turns out I had already posted the correspondence with Bob Pease.

You'll find the Tantalum measurements along with Bob's scrawled comments here: https://www.ka-electronics.com/images/p ... ence_2.pdf
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AnalogJoe
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Re: Classic Bead Tantalum Capacitor Failure

Post by AnalogJoe »

mediatechnology wrote: Wed Jun 03, 2020 7:51 am Turns out I had already posted the correspondence with Bob Pease.

You'll find the Tantalum measurements along with Bob's scrawled comments here: https://www.ka-electronics.com/images/p ... ence_2.pdf
Wayne, those are real gems right there! I enjoyed reading that, thanks!

I have an AP-1 system, you just encouraged me to start making some Tantalum measurements of my own.
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Audio1Man
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Re: Classic Bead Tantalum Capacitor Failure

Post by Audio1Man »

Hi AnalogJoe
The AP S1 has Tantalum only as pass modes and they are common failures. Sometimes the 15 volt trace also opens on the SINP assy. When I repair/service them I replace them with Panasonic low ESR parts. Tantalum’s is also prone to failure where ripple currents are present. When we developed the S1 in 84 alum caps were poor in HF bypassing.
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Re: Classic Bead Tantalum Capacitor Failure

Post by emrr »

I didn't remember seeing the Pease correspondence, thanks.
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mediatechnology
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Re: Classic Bead Tantalum Capacitor Failure

Post by mediatechnology »

Yeah I think I posted that back in 2007 or 2008.

Its fun to read some of the old threads...
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