[Boatanchors] 2013 myth

[Glen Zook]

Among Collins equipment users of which I know, virtually every one agrees that the black beauty capacitors in the 75A-4 need to be replaced.  Finding one that is not leaky is definitely the exception.  It has been my experience that other "paper" capacitors need to be routinely replaced as well.  Even if a particular paper capacitor tests good, it is still a time bomb waiting to "go off"!  Replacement capacitors are inexpensive and it is considerably easier to replace all the paper capacitors at the same time rather than do the replacement piecemeal.  Also, there is a very definite chance that if a paper capacitor shorts, it will "take out" other components some of which are very difficult to find replacements.

Bathtub capacitors generally last considerably longer than other paper capacitors.  However, it is also my experience that those are starting to go bad on a regular basis and I am now replacing them along with the other paper capacitors.

Silver mica capacitors are also going bad on a regular basis with silver migration being the principle cause of failure.

For those who just have a piece of equipment sitting on a shelf to "look pretty", then leaving the original capacitors is fine.  But, if the equipment is actually being used, then, in my opinion, it is foolhardy not to replace the capacitors.

Some resistor types are very prone to changing values while other types do not change value.  One has to remember that the original tolerance of the vast majority of resistors was +/-20% so the exact value probably will not be exactly what is indicated.  But, if the value is outside of the tolerance range, then that resistor should definitely be considered for replacement.
 
Glen, K9STH


Website:  http://k9sth.com


________________________________
 From: rbethman <rbethman at comcast.net>


 On 07/07/2013 05:49 AM, David Knepper wrote:

This “hysteria” concerning replacing the so-called “black beauties”, etc. frankly is like the man who washes his car every day so as to believe that somehow this will increase gas mileage!

David,

You are implying that you have "black Beauty" caps that test good. Are you actually saying that?

Bill KU8H


Morning,

Still consuming my morning coffee.

However, "Black Beauties", "Bumble Bees", "Brown Beauties", and "Tiny 
Chiefs", ALL fall into the same category!

There is NO myth. Just "junk" that either leaks like a sieve or just 
plain shorts!

Is David now an Audiophool? I can send him those I remove so that he can 
keep his Collins gear in "original" condition.