Cleaning Copper Contacts?

[Chuck Guzis]

On 10/2/2005 at 2:47 AM Martin Scott Goldberg wrote:

>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.

The PCB looks to be of the plain old phenolic variety, still used today in low-cost applications requiring only one or two-sided conductors.  It can be brittle, particularly with age, so be gentle.

The contacts themselves appear to be simple tinplate.  Try cleaning by gentle rubbing with an ordinary pencil eraser--that should remove enough tarnish to ensure good contact. 

Cheers,
Chuck