-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 19/01/16 12:34, J Martin Rushton wrote: > Not new: I can remember seeing DEC engineers cleaning up the > contacts on memory boards for a VAX 11/782 with a pencil eraser > c.1985. It's still a pretty standard first fix to reseat a card or > connector. I used to do that as well. The contacts would come out nice and shiny when you clean them. Then I found out that what I was actually doing was removing the very thin layer of gold plating on the contacts and revealing the copper underneath. That's why you should never clean contacts with a pencil eraser, just re-seat the boards and they'll make contact again. Peter -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQEcBAEBAgAGBQJWnYXFAAoJEAUijw0EjkDv+4EH/0wbRnoM9KePC0UUhViIdFZ1 cpaVvNqre+zVd6qBhnzbcPT+lXINHZ5Mm/Rw0tcBqx8nYzYab5qS5hTRaZOTm6H/ aXbH6shJC4o1LW/fGDkMZ0V8ZGgz4uN4cdMYN87rVqX+J477Igs3D4yO9Gxux6K7 Eqn3+kBECL5iBiFdOf86H0UoNZuUHkfMpj95R4AJnywTCqB5W1XaVQPViNs/ge16 5Ipk7uopfbREM+F60hI889XH3s0eUXabZsTUGJWE/nUd/sNCdnAqBVD3aTuwz6gv sb599qH8AAFX8pz0DloslLVQRb0pExbAHGM/IDMMwi1aJHGtbSDtphrt369aKJo= =5+bz -----END PGP SIGNATURE-----