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Hi Chris,
Have you disconnected the trace rotationcoil? This is causing a small magnetic field which might produce a small shift from the center. This coil is operating with a dc voltage of + and - 8,6 V.
There might be something wrong with this supply voltage.
Also you have to connect all vertical and horizontal plates to earth, avoiding a static charge on those plates.
Hope these suggestions might be useful.
Fred

On 10 mrt. 2019, at 16:49, Roger Evans via Groups.Io <very_fuzzy_logic@...> wrote:

Chris,

Has the scope functioned correctly and stably since in your possession (ie before the power supply blew)? The spot is so far off centre with no voltage on the deflection plates that it could be there is some internal damage to the CRT. If something is loose internally then the motion of the spot should correlate with moving or tapping the scope.

Roger

These are what I use. They are due in in June.



On 3/10/2019 2:10 PM, Reginald Beardsley via Groups.Io wrote:

I have been unable to find anyone who has these in stock selling just 2.? I've checked Digikey, Mouser, Newark, Arrow, and any other places google turned up.? ST said Arrow has them, but Arrow says otherwise.

Futureelectronics.com says they have them for $13.50 each, but with a 12 piece minimum.

There are lots of them on eBay from China, some with 1999 date codes.?? And I wouldn't trust more recent date codes on anything from China.? Far too much history of remarking.

These are the cure for E5622.? Is anyone else interested in getting a pair?? If so, please contact me off list.

I'm in Arkansas so it would cost $3.50 for me to ship them priority mail.? So a fresh pair would be $30.50 shipped.? These seem to have a useful life of 5-10 years.? I had to replace NVRAM in a Sun workstation in the past.? So I'm all too familiar with these things.

Reg

I have been unable to find anyone who has these in stock selling just 2. I've checked Digikey, Mouser, Newark, Arrow, and any other places google turned up. ST said Arrow has them, but Arrow says otherwise.

Futureelectronics.com says they have them for $13.50 each, but with a 12 piece minimum.

There are lots of them on eBay from China, some with 1999 date codes. And I wouldn't trust more recent date codes on anything from China. Far too much history of remarking.

These are the cure for E5622. Is anyone else interested in getting a pair? If so, please contact me off list.

I'm in Arkansas so it would cost $3.50 for me to ship them priority mail. So a fresh pair would be $30.50 shipped. These seem to have a useful life of 5-10 years. I had to replace NVRAM in a Sun workstation in the past. So I'm all too familiar with these things.

Reg

Hmmm?

The channel switch (MUX) is about the only part of the scope
where both the Vertical and the Horizontal signals are used
together.

However, the Horizontal position control has no part of the
channel switches operation, and yet the distortions are firmly
fixed to the position on the CRT's screen. You can move the
image frame right and left across the screen, and the distortion
still remains nailed to the graticule position of the beam.

So, no I don't think this can be anything to do with the vertical
and horizontal signal paths. It has to be a distortion within
the CRT itself.

I think it is one of the following:

1) physical abnormality inside of the CRT.
2) incorrect bias point for the quadrapole lens.
3) a stray magnetic influence.

The CRT is extremely sensitive to magnets put near the
face plate of the CRT. They can easily move the beam several
tenths of a division.

I suppose it could even be something as stupid as the current
traveling through the wires for one of the trace rotation coils.
They pass inside of the mumetal shield... though I don't think
it is really all that likely. The answer would only be a
connector pull away.

-Chuck Harris

Just another idea:

the vertical position is coming from the analogue multiplexers, not?

If so, can it be a drift of the output of the mux during the sweep?

So, maybe a faulty mux?

Just my two cents..

Leo

On 10 mrt. 2019, at 16:49, Roger Evans via Groups.Io <very_fuzzy_logic@...> wrote:

Chris,

Has the scope functioned correctly and stably since in your possession (ie before the power supply blew)? The spot is so far off centre with no voltage on the deflection plates that it could be there is some internal damage to the CRT. If something is loose internally then the motion of the spot should correlate with moving or tapping the scope.

Roger

I settled the grid issue, to my satisfaction, by hooking a
1 division square wave to the CH1, 2, and 3 inputs, turning
on the CH1-4 display, and triggering on AC mains.

I adjusted the vertical positions so that the pair of lines
visible for CH1-3 covered the lower graticule lines, and the
baseline trace covered the upper graticule line... leaving
out the top most, and the bottom most graticule lines, as
tek doesn't seem to think them relevant.

I then adjusted the time cursors to the first and last
graticule line, and the full picture of the distortion became
visible.

Lets number our horizontal graticule lines as follows:

outer most top line we ignore.
1-4 where 4 is the center line.
4-7 where 4 is again the center line.
outer most bottom line we ignore.

My CRT is almost perfect on line 1, but grows more and more
bowed to a peak at line 3, where it grows less and less
bowed to a straight line at line 5, After line 5 it starts
to bow downwards, to line 7 where it is bowed a little.

As to physical damage:

The 2467 CRT is built like a brick outhouse, except in 4 elements.

These elements are fringe shields for the vertical and horizontal
deflection plates, and are basically V shaped channels that are
positioned at the sides of each plate pair... in other words,
they cover the space between the left and right horizontal plates,
and the up and down vertical plates.

These shields are connected to anode1, and can be seen on the CRT
schematic as dashed lines.

Anyway, these are longish structure that are only fixed on one
end.

Everything else in the CRT is fused to the heavy glass rods that
define the positions and structures of the CRT.

-Chuck Harris

Harvey White wrote:

On Sat, 9 Mar 2019 21:38:36 -0500, you wrote:

Two frame calibration standardizers will work, I think, certainly one
will give you horizontal lines. I seem to remember using two of them
and getting a grid. Different scan rates, though.

Harvey

Hi Rolynn,

There is no setting of the geometry that will allow
my 2467B to have a straight horizontal trace in the
center of the screen. It either bows up a little bit,
or it bows up a lot. The switch between bowing up and
bowing down is about 2 divisions from the bottom of
the CRT.

Chris,

Has the scope functioned correctly and stably since in your possession (ie before the power supply blew)? The spot is so far off centre with no voltage on the deflection plates that it could be there is some internal damage to the CRT. If something is loose internally then the motion of the spot should correlate with moving or tapping the scope.

Roger

On Sat, 9 Mar 2019 21:38:36 -0500, you wrote:

Two frame calibration standardizers will work, I think, certainly one
will give you horizontal lines. I seem to remember using two of them
and getting a grid. Different scan rates, though.

Harvey

Hi Rolynn,

There is no setting of the geometry that will allow
my 2467B to have a straight horizontal trace in the
center of the screen. It either bows up a little bit,
or it bows up a lot. The switch between bowing up and
bowing down is about 2 divisions from the bottom of
the CRT.