Hazeltine Green

On 01/10/2012 07:08 AM, Popeye Theophilus Barrnumb wrote: It's standard P1 phosphor used for CRTs. P1 phosphor is a medium persistence green used for many CRTs and common in older oscilloscopes (most common was the 3ap1 and 5up1/5rp1). The CRTS used back then for data terminals were 13 or 15xxP1 types where the XX were one of a large set of letters used for magnetic deflection CRTs of various deflection angles. Other CRTs were the P5(short blue) P7 (short blue, long yellow[ish]) common for radar applications and P4 (black and white TV). FYI: the persistence was a factor in color choice. The green P1 was about right as was P4 the amber/orange had too long a persistence and made for very smeary looking screens. The Short blues were prone to flicker and hard to look at for hours. it was the mid 80 when Color CRT phosphors were applied to monochrome tubes and DEC had a very good Amber and a shorter green for the late VT100- and the VT2xx series would add a whiter white (DEC paper white). Generally pre 1979 all Hazeltine green monitors/terminals were P1, they also did an white P4. I can say this as I worked there for a while (15xx and 14xx terminals). I used a lot of 1100 and 1200 series terminals. Allison