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On Fri, Nov 23, 2018 at 01:59 PM, <tekscopegroup@...> wrote:

Added 4 pictures to my photo album showing rise time measurements of the 2465B
(o.57nS) and also my 2247A (~2.0nS). BTW the 0.57nS rise time was confirmed
with the corresponding parametric measurement, the result was exactly 0.57nS
as well.

That's not rise time you're seeing or "measuring", it's more like slew rate and what looks like the amplitude of the pulse really isn't.
Rise time is measured between two *stable levels* (usually, between 10% and 90% levels of it), whereas your generator generates a pulse with a duration that is relatively short as compared against the 'scope's rise time. On a faster 'scope you'll see a larger amplitude than on your 2465B, more towards the actual pulse amplitude. The parametric measurement assumes you're providing a step voltage; it cannot see the shortness of your pulse.
A pulse generator is not suitable to measure rise time, unless the pulse stays on its steady levels long enough, i.e. at least 2 ns or so for the 2465B.
A realistic rise time with an infinitely fast step applied would be more like 0.8 ns for the 2465B.
Assuming a theoretical rise time of your pulse generator of 0 ns (!), your 2465B's BW would be over 600 MHz. Even with Tek's usual conservative specs, 600 MHz + is not realistic.

Likewise, 2 ns for your 100 MHz-specified 2247A is not realistic. It would imply a BW of 175 MHz.

Just for fun, compare the amplitude as shown on both 'scopes. Don't forget to put both 'scope's vertical sensitivity settings out of "variable" for that.

What you *can* conclude is that the pulse slews faster than both your 'scopes.

Raymond