On 18 Apr 2005 at 15:40, Vintage Computer Festival wrote:
HP CRTs (especially the elongated ones found on the
mentioned machines)
seem to be more typically susceptible to this effect than other CRTs.
I wonder what it is about them?
They were all made by Clinton Electronics of Rockford, Illinois?
I have an HP 2640A, a couple of 2645As, a 2647A, and two 64000s; all have
spots to varying degrees, and all of the tubes were made by Clinton.
Any chance your ADM 3A tubes have Clinton stickers on them?
-- Dave