[cctalk] Re: Another 780 backplane story

Had another odd one with our 780. FE came in replaced board tge remote diagnostics called out and everything was good again. When he looked at the bad board he started laughing. One of the IC’s had a hole in it. Looked like it burned out. He said it was the first time he’s ever seen that! Sent from my iPhone > On Jul 4, 2025, at 14:21, Wayne S<wayne.sudol(a)hotmail.com> wrote: > > I didn’t see chalk, but it was $1600/hr plus expenses to know where to sweep. > IBM was paying it! > > Sent from my iPhone > >>> On Jul 4, 2025, at 13:44, Fred Cisin via cctalk<cctalk(a)classiccmp.org> wrote: >>> >>> On Fri, 4 Jul 2025, Wayne S via cctalk wrote: >>> This is similar to an IBM mainframe story i have. >>> IBM 370 wouldn’t IMPL. >>> CE and FE couldn’t figure it out. >>> They called in a “Special Consultant.” >>> I >>> Came in with a briefcase that contained his “tools”, which was a big brush that you would use for light plaster work and a wood mallet. >>> He proceeded to sweep the brush across the wirewrap backplane and a wire cam loose. >>> He replaced the wire and all was good again. >>> I never found out what the mallet was used for. >> . . . and a piece of chalk? >> measure from top edge, measure from side edge. >> Make a chalk mark. >> Hit with mallet. >> "$1 for hitting with mallet; $499 for knowing where to hit"