--- In firstname.lastname@example.org
, David Gesswein <djg@...> wrote:
> Looking in through the side the first couple of cards were being pressed
> by the foam. The foam was stiff but the amount they were pressed in wasn't
> that far. The later cards didn't seem to be pressed at all. I didn't see
> anything obvious indicating the foam caused the problem but it was removed.
I looked over David's shoulder at the work he reported and got similar impressions. I was concerned that the "foam" - actually more like rubber anti-static matting which is heavier - was so unyielding, that it pushed some of the one-width cards sideways out of position or contact. The two-width and four-width cards can't be pushed "sideways" in that fashion. I believe I suggested removing that material; I saw it was removed in any case.
The 11/20 is challenging in that the front panel is upside-down relative to the cards. Thus if the 11/20 is mounted for use, the cards hang "under" the backplane. It may be that *soft* foam is needed (not necessarily antistatic) to hold the cards in place. More DEC-11 experienced people can address this.