Connectors: Both contact surfaces must also be the same material?

[Jon Elson]

On 07/10/2016 01:58 PM, Al Kossow wrote:
>
> On 7/10/16 1:14 AM, Paul Birkel wrote:
>
>> Almost every DEC System Unit ("backplane") that I've ever seen uses
>> tinned-contacts, yet the Modules all use gold-plated fingers.
>>
> I'm not near one right now, but there should be gold plating on the finger in the DEC
> connector block at the point of contact with the pcb edge connector. It's easier to
> see on the VAX era blocks.
>
>
Absolutely.  The WW pins were tinned, but there was 
selective gold plating on the card edge contact fingers.
It would take a strong light and magnifier to see it down 
inside the connector, but you can rest assured the contact 
was gold-gold.

Jon