I finally found a new video output board for my CCII. After installing it, I adjusted the G2 and let it be to see if the problems I had before were actually caused by the previous board. After about 10 hours of problem free viewing, I was confident it's now fixed.

So now the next issue......I need to adjust the color drives. With all drive controls down, there is a green tint. So I'm assuming the green drive has more output than the red and blue. Since all controls are at minimum, I have to adjust the other two colors. This leads me to my question about how to best adjust the two other colors to get a white raster.

I've tinkered with the red and blue, but always seem to find the screen either a bit too red or blue. I've tried it with the grayscale pattern of Video Essentials as well as a black and white movie. Either way I don't seem to be able to get the whites white and the blacks blacks. There's always a hint of blue or red. I must be missing something or expecting too much.

Any assistance would be greatly appreciated.

Thanks

Sometimes the tracking isn't uniform at different brightness-control settings. In that case it would be best to set it up at the part of the brightness pot which you use most.

It's always a bit of a compromise, IME...but you should be able to get it very close unless the crt is weak or there are other problems.

what color is the crt face?if slightly green,then your b/w should be slightly green to start.a little tweaking until you get it to your liking.i like mine very slightly blue.start out with red screen,then mix green in until the screen is uniformly yellowish green,then mix blue until gray appears.service line adjusting is what i use.this is a personal preference and with a ccII you should be able to get it on the money if the crt is good.actually with a zenith,even a bad crt will look good!

Sometimes, with either all the screens down or the drives you can still have a gun that appears to be a little "hotter". Since you adjust the screens first you can disable the drives (sometimes easily) to get the screens most uniform then connect up the drives and only bring up the others to the point of intensity of the "hot" gun, and adjust up from there.

It is good to have the brightness control centered for starters, but if the range isn't there then you can always go up on the Kine Bias switch/pot too, or after your initial settings if tracking is poor or brightness is still low.

After all of this, if retrace lines are appearing then turn the Bias down.

If you have all the screens down and you see a hot gun other than red, you can load down the screen with a 100K resistor so you can set purity. The old school TV guys would rig up a box with 100K's in the and a toggle switch for switching off the guns. Some old troubleshooting books will go through this too.

If the tube is good and tracking well, you should be able to go through the range of brightness and maintain it gray scale.

If you don't like the results you can always repeat. If the tube has been rejuvinated or has a new gun, it may settle in a bit and you're re-adjusting again!

Then there's always that "It don't look right" and an hour later your still fussing over it!!

It's been awhile since I've gone through the process but you know the drill..!!

...

Mine is a CCII of later design (so I've been told). Something about the socket that fits over the tail of the CRT. The video board has one G2 and three color controls (the manual calls them tracking controls).

The tube tested good and I don't think there are any other issues with the unit. Over a year ago the tripler went out and took the socket on the video board with it. The new tripler is working like a charm, but he replacement video board wasn't so nice. This new one seems stable (haven't had any color bursts, blotches, etc.).

Basically, the manual tells me to adjust the G2 before attempting to adjust the color tracking controls. It says to place the brightness control to full to get a raster on the screen. Then based on the color of the raster, adjust the other two color tracking controls to make a white raster.

I guess I'll be tweaking it for some time to come unless I can stop myself from looking at everything I view with a "critical eye."

Wish me luck. I'm going back in.

Thanks for all the help.

What CRT does this set have in it? I have several good Zenith tubes form that era that are headed to heaven.

Was it like this with the other video board? It sounds like something is still wrong on the chassis. It really shouldn't be that hard to adjust.

This is how I have been doing setup.

Turn the color control all the way down.
Set the brightness to max.
Set the drive controls in the middle.
Adjust the screen controls for the best black and white picture I can just a tad brighter than I like.
Turn the brightness control down to where I will be using the set
Fine tune the drive controls for the best black and white picture.

I dont use the setup switch line method anymore.

---

I was just generalizing. Just have to fine tune the screens.

...

With this design, you can generally get good tracking, but when the tracking is correct, you have no choice of the color temperature. In other words, the gray scale may be slightly off-color all the way from very dark gray to white.

Well I got the the b&w tracking to a point I can live with. First time around it was a bit on the blue side. When watching a movie, the dark scenes had a blue tint. So back to adjusting I went. The second time it was too red. And of course, the third time was the charm. I watched several scenes with varying levels of black as well as overall image quality (found that a poor quality image such as an old VHS showed the problem more). This time around I found only blacks and greys as it should be.

Thanks for the advice.

My method on those, was to set the G1s at midrange, turn all 3 G2s to min, color to min, and Chromatic switch off. Service switch on, and try all 3 G2s. If one doesn't show up, or if one is already there with G2 at min, turn down CRT Bias/bright limiter (on the socket board if yours is a 9-121, or on the chassis if it's a conventional socket on the tube) until it's out (or up until weakest one can be turned up with G2). Turn the 3 G2s to a very dim white line, then turn the service sw to Normal. Turn the picture (cont) to min, and brightness to max (or a bright, washed out picture). Set G2s slightly for best gray, then turn up the picture and set G1s for best whites. Repeat 2 or 3 times if the set is being Irish.

This is slightly off from the book procedure, but I like it better on those bright Zenith tubes.

***BEWARE: Those G2 pots are VERY FAMOUS for being burnt. If you get one that doesn't turn nicely up & down (acts like an "ON-OFF" switch in stead of a control), you need to replace the pot.

Charles

My method on those, was to set the G1s at midrange, turn all 3 G2s to min, color to min, and Chromatic switch off. Service switch on, and try all 3 G2s. If one doesn't show up, or if one is already there with G2 at min, turn down CRT Bias/bright limiter (on the socket board if yours is a 9-121, or on the chassis if it's a conventional socket on the tube) until it's out (or up until weakest one can be turned up with G2). Turn the 3 G2s to a very dim white line, then turn the service sw to Normal. Turn the picture (cont) to min, and brightness to max (or a bright, washed out picture). Set G2s slightly for best gray, then turn up the picture and set G1s for best whites. Repeat 2 or 3 times if the set is being Irish.

This is slightly off from the book procedure, but I like it better on those bright Zenith tubes.

***BEWARE: Those G2 pots are VERY FAMOUS for being burnt. If you get one that doesn't turn nicely up & down (acts like an "ON-OFF" switch in stead of a control), you need to replace the pot.

Charles

I'm assuming that the G1s you mention are not available on my set (chassis 19JC55Z). I have one G2 (yellow pot) and three color controls (R, G & B) all located on the CRT mounted video output board. There's a setup jumper on the board for adjusting the G2 and a hi/lo jumper for the G2 range.

I do have a brightness limiter (on the chassis), but the SM says to adjust it with a 10K pot wired as a rheostat with an inline 2.2K resistor and adjust for a max voltage of 1.5V. The brightness range is on the AGC module is easier (adjust for a dim raster).

So far I am good with the adjustments I've made. Not 100% sure I've got them all adjusted for optimum viewing, but at this point I feel I could only make it worse or get the same results. I don't have enough hands on at this point, but I'm learning.

I do wish I didn't live in L.A. as they throw away everything for the next must have item. I've been looking for a nice Avanti set, but nothing has shown up locally.

Thanks!