Cleaning Copper Contacts?

[Martin Scott Goldberg]

>>My concern is I don't want to use any sort of cleaner that will harm
>>whatever material the surrounding pcb is made of (as it appears to be made
>>out of an older, thicker material than most modern PCB's I see).
>
>If the underlying material is copper, why not one of the ion-exchange instant silverplate solutions like Cool-Amp or Caswell Silverplater?  They deposit a very (one molecule) thin layer of silver that might do the trick for a restoration.  Caswell also m
arkets brush-plating electrolytic silver (and nickel, gold and a whole bunch of other metals) kits if you'd like something more substantial..  (http://www.caswellplating.com).
>
>Cheers,
>Chuck
>

The exposed copper doesn't look to be underlying.

Well, here's a pic of what the cart and connector normally looks like -

http://www.pong-story.com/pics/odyssey/cart7.jpg
http://www.pong-story.com/pics/odyssey/carts.jpg

As you can see, the PCB is much thicker than a standard PCB of today.  I'm
assuming its made of a different material then (which is why I'm hoping
people on here in to mini's and such from that period of around 1972 would
be familiar).

The contacts themselves are what are tarnishing and turning green, some
with white deposits.

Marty