Re: MCP and CRT Readout


 

On Sun, 28 Jul 2013 21:23:22 +0200, "cheater00 ."
<cheater00@gmail.com> wrote:

On 28 Jul 2013 20:55, "David" <davidwhess@gmail.com> wrote:

On Sun, 28 Jul 2013 20:34:35 +0200, "cheater00 ."
<cheater00@gmail.com> wrote:

On 28 Jul 2013 20:13, "David" <davidwhess@gmail.com> wrote:

The 7L5, 7L14 and 7L18 spectrum analyzer plug-ins have storage so they
should not be used. In general *any* plug-in which generates a slow
continuous sweep or vector graphics should not be used which would
include the 7L13 spectrum analyzer which does not have storage.

The readout is vector generated but considered a necessary evil and
only affects the top and bottom border area of the CRT.
Thanks, makes sense. What if one modulated the signal e.g. with a sine
wave... might not be so damaging then?

Given readout is fully digital. I'm surprised no one came up with an LCD
readout mod ... 20 years ago.
My understanding is that the MCP cells just have a finite limit to the
number of electrons they can amplify so damage is cummulative with the
gain in each cell diminishing over time. In a continuous tone
application like a low light image amplifier tube, this is not as
serious a limitation because the whole MCP will tend to wear evenly
but with an oscilloscope, wear is limited to very sharply defined
areas where the CRT beam scans.

I think later MCPs were a lot tougher than the 7104 MCP.
Does this mean the 11302 and 2467, or were there even later MCP CRTs?
I mean later MCP CRTs which are still used in some specialized
applications. I base this on the links posted here in a MCP
discussion thread some time ago which discussed MCP lifetime and
wearout mechanisms. I suspect the MCPs Tektronix used had unusually
short rated lifetimes but maybe they wear out quickly because of how
they are applied.

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