On Tue, Mar 9, 2021 at 12:19 PM, Jean-Paul wrote:
Wide bandwidth example 2467B or 7104, 400 and 1 ghz BW, microchannel plate CRT
but smaller display
I guess that the screens of the 2467 and 7104 are smaller not so much because of BW requirements but because the angle of incidence of the electron beam varies more across a larger screen, affecting the "transparency" of the microchannels and thereby the MCP's gain across the screen.
The 2445B and 2465B, both with 400 MHz BW, have a larger screen size, as do the 400MHz and 500 MHz instruments in the 7000 series (7844, 7854, 7904(A)). Smaller screen size allows higher brightness (writing speed), witness models like the 7904 option 4, with its smaller (4 x 5 cm, instead of 8 x 10 cm) graticule. 24 kV total acceleration potential helps as that model...
Analog storage CRT's often have a smaller screen as well (7613/23/33 vs 7603!).
BTW: Models like the 2430/32/40, with their modest BW requirements, use the same complex CRT as the 2445 and 2465. I guess that's to do with CRT availability...
Raymond
Raymond Domp Frank