On Tue, January 19, 2016 18:36, John R Pierce wrote:

On 1/19/2016 3:29 PM, J Martin Rushton wrote:

...

I suspect that the gold layer on edge connectors 30-odd years ago was a lot thicker than on modern cards. We are talking contacts on 0.1" spacing not some modern 1/10 of a knat's whisker. (Off topic) I also remember seeing engineers determine which memory chip was at fault and replacing the chip using a soldering iron. Try that on a DIMM!

indeed, I pretty much quit doing component level electronics when everything went to surface mount.

Kids these days! I remember taking the vacuum tubes to the testing centre in the corner drug-store to see which ones need replacing.

Apologies to the four Yorkshiremen.