Problem with all my KY- JVCs: Black or magenta bar on the left

[dauberich]

Hi.
After I have gathered now seven KY-CCD- Camera from JVC I come to the conclusion that there are two types of common "effects" and a common problems with all the chips - trough all sizes and all generations. My cams: GY-X1, GY-X2, BY-10, KY 15, KY-17, 2x KY-27

First is a visible, but not very strong tendency to end up with warmer mainly, red tinted whites if the picture is overexposured or has many bright parts in it.
I will try to find out whether it is possible to adjust this behaviour in the settings - even it is not that dramatic. Maybe it is a phenomenon all JVC cameras show from a certain age, and they are all older the 20 years..

Second and more annoying problem is a vertical black or magenta- colored bar that is not that much visible at 0 db and a cold camera, but can become visible with a warm camera and especially a high gain settings. The "size" is about the same a one or two bars from the color bars. (First example, KY-27 at 18dB)
Using the lolux function (if given) the bars become strongly visible and the picture is almost unusable. In that state the bars even become "echoes", meaning that there is not only one bar at the left but up to two or three bars with a lower level but still visible and also destroying the picture. The space between the bars can "infected" too, meaning that the black level is slightly increased as well. (The the second example). I took the pictures from a Barco showing a lens cap- picture of the cam as it is to be seen the best in black. But it is also visible in gamma and white.
Of course, I thought about the shading adjustment, but from the space the problem takes I don't not believe to be able to compensate it by that as any shading adjustment will effect a wider part of the ine but not only the left with a so hard edge to the "untouched" part of the picture.

Well of course that is not really a problem as non of the cameras really has a “job” to do (..if you leave out standing-around-in-the-showcase as a job) but as all collectors I would like to see the camera performing as good as possible - and I guess the cams can do better - as they would have never been sold with an effect like this.

So.. Does anybody know this problem? Does anybody know where it comes from and whether it can be adjusted or fixed? - Thanks for your ideas on that!

Stefan

[old_tv_nut]

I don't know what to say about this. The second picture looks like the kind of ringing you might get from a tube-pickup camera at high gain, but you say these are all CCDs, correct?

The tinted whites could be due to the different color paths saturating at different levels, but generally I think one would expect the red to saturate first in a CCD, making the highlights turn cyan or blue. so, I am at a loss to explain that too. Maybe there are white clipping adjustments somewhere?

[wiseguy]

I used to work on lots of these.
you need to replace all of the Mini capacitors all over, then the Encoder board will have to aligned, the red problem also sound like bad cap in the red white Clip circuit, most times you can replce the capacitors and it will looks fine without alignments, unless you want to match 2 cameras the same

[TV_Engineer]

I agree with wiseguy. You have flunky caps. This is not uncommon with all of the Japanese equipment from the 80s through the 90s. Early Panasonic DVCPro decks were stuck with this issue too.