7JP4 Tube Grading

[N2IXK]

Did any rebuilder actually produce "Grade A" color CRTs? This description:

Grade A— Used glass envelope, new or used shadow mask, all other components and materials are new.

would indicate that the tube was rephosphored. Depositing a new tricolor phosphor screen would seem to be FAR beyond the capability of CRT rebuilders. The shadow mask was actually used as a stencil in a multistep photoresist process to locate and deposit the dot triads in exactly the right locations. This would involve separating the faceplate and mask from the funnel, rescreening the phosphors, and then resealing the tube together using a frit seal process as the OEM did. Sounds like WAY too much work to be economically viable.