Matt Pobursky wrote:
> On Sat, 10 Nov 2007 10:04:11 -0500, Dave Lag wrote:
>   
>> Bob Axtell wrote:
>>
>>     
>>> Does gold make a difference? yes, but not initially. When a pin is
>>> initially crimped, the tin/copper (wire) interface
>>> is acceptable. But with time , the tin corrodes, whereas the gold
>>> (being malleable and inert) maintains a good
>>> connection. The fact that time is a factor causes even the best of
>>> engineers to overlook the advantages of gold pins.
>>>
>>> For the record, Molex DOES make some good pins (but KK isn't one of
>>> them).
>>>
>>> --Bob A
>>>
>>>       
>> For the 0.156" I have been using a KK contact with 3 wipers. Yes, do wish
>> they made the same for 0.10". Even the C-grid grabs from 2 sides....
>>     
>
> Molex used to make a "box contact" for the 0.1" KK series connectors with
> multiple wipe contacts. I used them in the distant past but didn't find
> they performed any better (or worse) than the single leaf style contacts.
> You might check their catalog to see if the still make them. I know that no
> one used to stock them and we had to order reels of them so they may still
> be in existence but hard to find.
>
> Matt Pobursky
> Maximum Performance Systems
>
>   
Good comments.

There was solid analysis done on what was happening to the kk 
connectors, using a laboratory to assist
us. What was happening was that high current sometimes flowed through 
some of the connector pins. Over time-
and not much was needed- the springiness of the connector faded due to 
the high current it was handling,
and the contact pressure lessened and lessened until there was almost NO 
electrical contact. I decided
that if the connector had been sturdier, the problem wouldn't have 
occurred, although we could have
fixed it by (1) better sharing the load at the connector pins; (2) 
replacing the post with a gold-plated or
smoother one (high spots on the post plating were contributing to "hot 
spots"); increasing the number of
pins used. We fixed it by replacing the post AND the connector type; I 
wanted berg MiniPV but the
client settled on a quality AMP gold connector and a gold-plated post, I 
think from 3M. In any case, the
problem completely went away.

--Bob A

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist