[Premium-Rx] Replacing old tantalums?

[GandalfG8 at aol.com]

In a message dated 13/04/2009 20:34:21 GMT Daylight Time, greer86 at att.net  
writes:

I would  say use Mil spec M39003 or M39006 parts when possible.  ePay 
sellers  
generally have them.  One of the advantages is that if one fails it  is not 
going trash the circuit board in it vicinity as the infamous red  end ones 
do 
in older WJ equipment.
--------------
More often than not, especially for kit out  of active service, it isn't 
even really necessary to  replace tantalums with tantalums.
 
Capacitor technology has improved somewhat since the 70s and most failed  
tantalums used for filtering could just as well be replaced with an  
equivalent "normal" electrolytic.
 
Although I do like to keep equipment as original as  possible, so would 
usually refit the "correct" part later, I've  got myself out of trouble more 
than once by using a more  modern electrolytic that's to hand.
The voltage rating is what's most important, as long as it physically  fits 
even the capacitance value isn't likely to be all that critical, within  
reason, in most instances.
 
Given the overkill often practiced in supply line filtering there's more  
than a fair chance with a single tantalum failure that you could just leave 
it  out and not make any difference:-)
 
regards
 
Nigel
GM8PZR