I found an old thread about 07MS/SD187 tubes in E-home ECP projos. Here is an excerpt
Can someone explain, in detail, what needs to be done? I had bought a complete new set of 187's for my ECP400, and UPS broke them, (imagine that!). Anyway, I have a claim in with UPS, and I figure if I am going to get them replaced, it might as well be with the 07's. I have actually already ordered (and received) the blue. I want the best performance I can get out of this, and this seems awfully important based on the above. Thanks!
|The difference between the 2 tubes as explained to me by Wayne Bickly at E-home years ago when they initially released them, was an improved phosphor coating for increased brightness and durability, and redesigned cathode grids also for slightly improved performance (although I can't remember why). The slight change in the way the tubes perform is the reason you have to cut off the inner plastic flanges of the defl and conv yokes and combine them together for improved convergence range, and replace the CRT sockets with the High Altitude sockets (otherwise you can get an occasional arc - very discomforting). The stig/flare rings also need this slight shift forward for max beam spot performance. Without these mod's, you can still get this thing aligned, but you won't realize max performance. In every upgraded ECP I have done (which numbers into the above 500 territory - Jeez, I'm tired), I have seen a noticeable improvement over an equally new sd-187 setup. IMHO, they're pretty nice tubes.... hope that helps|