Thanks Michael, Albert.
Michael, the data sheets for this tube do indicate that there are different phosphor options available for different writing speeds so I think that the speed is defined by the phosphor given that standard theory.
Albert, I believe that your observation of the suffix is true. As to why they offered both features is beyond me. As for a 5UP1 being interchangeable with the 5DEP1, I first thought that I could go ahead and pick a 5UP1 up but later found that it has a much lower deflection sensitivity. Otherwise it would be a fit.
There is one (F) tube on the auction site that I wanted to get and looks to be in good condition but the seller never responded to any of my offers nor emails. I think there might be a possibility that they may have fallen prey to the virus. Anyone else have this problem with purchasing things recently?
Greg
