[ARC5] Reforming Electrolytics attached as PDF

[Roy Morgan]

Bob,

One of the most experienced members of the Collins community reports a very high success rate reforming original electrolytics in Collins radios:

His method is to reform the electrolytic VERY SLOWLY, with a B+ source limited to FIVE MA., while monitoring the Cap voltage. Patience is essential. Reforming is at its limit when the voltage ceases to rise with increased current. 

This is NOT the common “bring it up slowly on a variac” method!

My experience using the 5 ma max method is also that the majority of electrolytics will re- form to a useful voltage. 

I would expect that a cap that reforms only to a voltage lower than its rating would work ok at a voltage lower than the reforming voltage by a healthy margin. 

I don’t have an ESR meter, but I expect that using one and the above method would take all the guessing out of working with old and new electrolytics. 

Note: I find that lower voltage electrolytics (6 to 30 volts) reform to voltages a lot higher than their rating. 

Roy sends.

> On Mar 19, 2018, at 8:27 AM, Robert Eleazer <releazer at earthlink.net> wrote:
> 
> I've been evaluating electrolytic caps by applying a  charge and then noting the results. 
> 
> 	
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