[Kenwood] Capacitor reliability

[Kenneth G. Gordon]

On 29 May 2010 at 11:33, John E. Cleeve wrote:

> Gentlemen,
> 
>             I apologise for this item being "off topic" but it does apply to
> the radio equipment we use.

IMHO, this is NOT "off-topic" at all. It most definitely and directly concerns 
those of us who are keeping "ancient" equipment in operation.

> I am in process of repairing the inverter of a
> TFT LCD display, and my diagnosis is that the problem relates to one or more
> of the miniature electrolytic capacitors mounted on the Chinese "Mirage"
> pcb.

Again, see http://www.badcaps.com/

You will find some very valuable information there.
 
> Perhaps I am being unduly pessimistic,

Although I can understand your concern, I DO think you are being a bit 
pessimistic....but only a bit.

> but it would appear that
> if you have a problem with your radio, then perhaps the first step in the
> repair process, may be to change the miniature electrolytic capacitors as a
> matter of course.

Not necessarily: bad caps of the miniature variety are, in general, easy to 
spot, if you know what to look for. 

See the above-given link for details. 

Fortunately, our older Kenwoods were built before the electrolyte formula was 
(partially) stolen and taken to China.

> Does any one have more detailed experience in this
> subject?  

Yes. Until I retired last month, I earned much of my living repairing computers 
and associated "bits".

A number of years ago, as I understand it, someone who worked at an 
electronic component manufacturer in Japan stole the formula for the 
electrolyte used in the construction of electrolytic capacitors and went back to 
China, where he sold that formula to many small and large companies there.

Unfortunately, he didn't get ALL the formula and it was missing some very 
critical component or two. Due to the missing component(s), the lifetime of 
these Chinese-made capacitors was reduced to sometimes as low as a few 
weeks. When they failed, they would do sigificant damage to the associated 
circuit board.

Yet, since the cost for these defective caps was less than 1/2 of those from 
the more reputable makers, the majority of the computer industry bought and 
installed them by the billions.

Very shortly thereafter, and for many years afterwards, computers, 
motherboards, peripherals, etc., started failing by the thousands. Many, but 
not all, of these failed items were covered by warranty, and some were 
replaced by that means. This cost the manufacturers millions.

We are STILL feeling the effects of this criminal activity.

Most folks whose computers crapped out, never were compensated, for 
various reasons...

However, in OUR case, what this means is that we MUST be very careful in 
our choices of replacement electrolytic capacitors for our equipment.

So, you see, the topic you have brought up DOES, most definitely, effect us, 
and IS something that should be brought up here.

Again, for those who may have missed it, visit the following URL for 
exhaustive detail:

http://www.badcaps.com/

Ken Gordon W7EKB