CurtPalme.com Home Theater Forum

[AFryia]

I've been lucky all these years and have only needed to use the electronic adjustments to get a decent picture on my G70.

Now I moved a good set of tubes to my service chassis to make that my main PJ. So I figure might as well go the extra mile and do the magnetics this time.

Problem, the Sony manual is poor and the diagrams worse. So correct me if I'm wrong here...

A - astigmatism tabs (astigmatism and luminance point)
B - CPC (2/4plole) magnets
C - Focus Coil (rotate to adjust the vertical)
D - Main DY Coil (rotate to adjust the horizon)
E - Sub DY coil
F - what is this tab used for?

[David_Web]

If it doesn't exist already it might be a nice idea to make something like this for most common tubes.
And also how to take them apart. (and put them back together)

[Brian Hampton]

Hi,

Regarding "A" It's only a 4 pole adjustment for astig. All 2 pole is done via EM controls. 4 pole is further refined with EM controls.

Regarding "C" this is the EM focus coil. It's not rotated to adjust vertical geometry but rather your 4PA 4 pole adjustments can make the spot shape longer vertically or horizontally and it's making the vertical of this to be true vertical. (There has to be a more elegant way to phrase that, sorry. I'm still having my coffee.)

Regarding "F" - I don't know. I've never adjusted that. Don't see anything about it in manuals. Let me know if you learn more.

Thanks and Good Luck,

Brian

[Brian Hampton]

Hey,

By the way,.. there's a spacer called wedge just at the front of the Em Focus Coil,.. that part is directional. It should support the front of the focus coil and sort of mate to it (it's beveled). Don't put it backwords or Em Focus won't work as well.

-Brian

[Brian Hampton]

Hey,

About "D" I think you will want to rotate the whole Main DY assembly which includes that black plastic stuff all the way back to the Em Focus coil. Once it's loose I usually rotate it using the nice big hunk of plastic. I wouldn't try to grip it closer to the point you labeled "D".

-Brian

p.s. EDIT - I think the Sony Manuals are actually great.

[AFryia]

Brian,

So you make your adjustments with power on?

This diagram from the manual (3-5) is nothing like a G70. It alludes to mechanically adjusting the 2 and 4 pole CPC.


I have another question. In an ideal setup shouldn't every electronic control be set to 128 (PIN,SKEW,LIN, etc.)? Not just Zone.

[WanMan]

The F tab is what brings hot women on the screen come into your home theater. Weird Science!

[Brian Hampton]

Hey,

yeah, I think you make all those with power on.

Yeah, The manual shows nice sets of CPC magnets but in reality they aren't physically there. Doesn't matter though. You can rough in the 4 pole with the magnets you've labeled "A" and then do the rest with EM Focus controls.

The notion of having all electrical controls nomalized or set to 128 doesn't wind up making lots of sense. I like the notion but aside from Zone all the parameters need to be adjusted to what's right for your setup. You can set horizontal and vertical skew to 128 and then tune with the Main DY but ultimately there will be a correct Key and Pin and Lin and such and you won't have a way of mechanically over-riding that.

On the Marquee there's a few more controls you can adjust before digging into the electronics like width of each color. The overall size of Green can be mechanically adjusted on the G70 but there's usually no reason too unless it's not letting you maximize the rasters as much as you want too.

-Brian

[Axatax]

Forget the manual - it's confusing and incorrect and several places. Here's how to do a mechanical setup of the G70 yokes so you'll be at a good starting point to do the electronic adjustments with something like the Holy Focus guide. I may have some of the EM focus control lables wrong, as I'm nowhere near my PJ now.

- Set all the yokes roughly vertical, and butted up against each other with the deflection yoke as far forward as it will go.

- Set the skew and EM focus controls to 128 and bring up the coarse crosshair pattern.

- Rotate the entire deflection yoke to make the horizontal line in the cross pattern horizontal within +/-5 steps of 128. Ignore the stuff about "sub DY" adjustment and the two side tabs. Lock it down.

- Go into the EM focus controls and ramp "ALL" to zero and DQP to "255". Rotate the EM focus yoke until the elongated dot in the center of the screen is vertical, then adjust AQP so the elongated dot is as thin as possible. Lock it down and bring the EM controls back to 128.

- Ramp up "ALL" to 255 and adjust flare using the rings, then ramp "ALL" down to zero and center the dot within the halo using 2PA/2PV. When "ALL" is at 255, you want the large dot to be as round as possible, and when "ALL" is at zero, you want the dot within the halo to be centered. You'll have to ramp "ALL" up and down and go through these adjustments several times to get this right. You'll be done when the dot doesn't move when "ALL" is run through its full range of adjustment, the dot is remains round when "ALL" is at 255, and the dot within the halo remains centered when "ALL" is at zero. Adjust "ALL" so the center dot is as small as possible. Lock it down.

All of these controls are also somewhat interactive. You mave to go back and touch up earlier adjustments, esp. after adjusting flare.

[AFryia]

[Axatax]

[AFryia]

[Brian Hampton]

HI,

DQP and AQP are 4 pole zone adjustments. I defocus the center(which affects the entire screen not just the center) to do 4 pole all about the screen and then I adjust EM Focus zones after all the 4 pole stuff is done.

2 pole is only adjustable in the center of the screen or zone 1. I believe that actually makes sense anyway as the 2 pole adjusts how the light passes through the focus lens while the 4 pole adjusts for inherent defects within the lens. Or ... something like that.



-Brian

[Heywood Jablome]

Isn't this covered Really Well in the G70 setup DVD somebody here has produced?

[Brian Hampton]

That's a 1292 setup DVD.

And.. yeah, I think it's cover-ed well. I haven't seen it though.

-Brian

[Axatax]

[AFryia]