I'll try to answer some of your questions,
On my Sony 1272, I assume the optical focus is with the lenses (R1/R2, Etc) So what is beam focus and how is it done?
it's electric focus, the 3 pots under the 3 screen or G2 pots, on right side of your sony, at the right of remote
So to focus or under focus the electron beam I use the lenses? I'm really confused.
you have to focus and underfocus with electric focus, I quote an explanation of astig adjustment posted by Chuck Williams (not sure):
What you want to see here is while moving the electronic focus from
100-0 and back to 100 the dots have NO movement on the screen. If they
do, you need to adjust the back ring to get the minimum movement.
As mentioned above, display a dots pattern. Set dynamic astigmation
controls to center position. This allows you to set the magnets to do
most of the work and just fine tune later with the dynamic controls.
Binoculars are very handy but must be of large light gathering power.
You'll need to significantly increase contrast setting to above normal
to see things clearly during astigmation adjustment. Also work with one
gun at a time. Cut-off the other two. Once astigmation is complete,
don't forget to return contrast to normal before final beam
e-beam focus to max one direction then the other. In one direction
(underfocused)the dots will become large circular or oval blobs with
brightness within the blob. In the overfocused direction, the spots
have a central luminous portion and a dimmer halo. These both need to
examined when doing astigmation.
The 2 pole magnets are the rearmost of the shaper magnets. These are
used to center the electron beam in the middle of lens. Place the
into overfocus to show the central luminous point and surround halo.
The 2 pole magnets deflect the luminous point. Twist the knob to alter the
amount of deflection. Rotate the knob about the tube neck to alter the
angle of deflection.
If you use a center cross pattern instead of a dot pattern when
centering the e-beam it's easier to see when the beam is centered in
A center cross shows up as fat lines with a central luminous line. Just
adjust the 2 pole magnets to make the luminous portion of the vertical
and horizontal lines centered within the fat linear halos. It's easier
to see than staring at a point with a halo.
The 4 pole magnets are frontmost of shapers. It is used to alter beam
shape to a circular shape. One sets the tube to underfocus and displays
a dot patter.
This turns the dots into a larger,uniform blob whose shape
is adjusted using the 4 pole magnets. Twisting the knob adjusts degree
of oblongation. Rotating the knob about the CRT neck alters the axis of
the effect. Make things as dead round as possible for the center
dot. Turn focus up and down and make sure things track correctly. You may need to
make some minor tweaks to the magnets to get things just right.
The astigmatism adjustent can seem difficult at first go but once you do one tube you will
easily do the other two. With a signal applied first call up the cross hatch pattern then
kill the red and green guns. Turn the blue pot SLIGHTLY counterclockwise to unfocus the gun
then adjust for beam centering with the neck rings. Then call up the dot pattern and turn
the blue pot clockwise past the sharp focus then agjust the other neck rings to get the
beam shape as round as you can. Then bring the pot back to focus and reset color bias to
get a white square.
Focus the dots as well as possible. Then go on to the next gun. When
all three guns are completed, you now have "static" astigmation
optimized and this means the dynamic astigmation system is under less stress.
Perform dynamic astigmation for each zone as well as beam focus.
Now that beam focus is optimized, it's time to recheck optical focus
for center, corner, and Schempflug (horizontal and vertical flapping)
You can check lens flapping by using the center lens focus (rear
wingnut). Display an inverse +pattern and adjust center focus to make
center of the top screen edge perfectly focused.Note the lens control
position. Next adjust the lens to make the center of the bottom screen
edge perfectly focused. Is it the same position. If yes, vertical lens
flapping is dead on. If the two positions are not identical, you need to
readjust vertical Scheimpflug (flapping). Similarly compare the perfect
focus positions for left vs right edge. Finish by adjusting center focus to
perfection and touching up the corners using corner focus (front
good luck Areno!!!