Moderators: Dave Moll, Andrew Davie, Steve Anderson
Klaas Robers wrote:Very good !
That you see the circle of the vidicon's target will say that your scanning is too wide. If you make the amplitude of the sawtooth voltages lower, the image will enlarge. This is a camera and of course this is opposite to the reactions of a monitor.
But first make that you can see something in the circle, so place a picure in front of your camera and try to focus the lens and then the focus current. Then you can center the picture mechanically and decrease your scan until you have got a screen filling picure.
Klaas Robers wrote:It should be such that if you decrease the peak-peak amplitude of the sawteeth, while the centre of the sawteeth voltage stays at the same DC-value, that the circle should get larger. Look well at the DC voltage of the middle of the sawtooth voltages, as if that changes too, then the circle shifts. May be you have to adjust two trimmer resistors at the same time, one for the amplitude, the other for the DC value.
And do it one by one, so first the horizontal and then the vertical sawtooth. At the end the circle should disappear completely and the corners of your picture will be at the circle or slightly within the (invisible) circle.
Adjusting the focus current will rotate your picture somewhat. You can adjust that by placing a variable resistor in series with the coil.
And all do these adjustments with the highest line numbers for the video. If you do this at 32 lines, you can't see any changes in the focussing. I did this always at 625 lines CCIR scan.
Steve Anderson wrote:I'm sure many know this - but the devices marked for example, c1216, are a shortened version of 2SC1216, there just isn't the space on the body to print the entire type number. Also applies to 2SAxxxx. These generally come from the far-east, Japan, Korea and others.
With the full type number you may have a better chance of finding the datasheet for them...no promises though!
Also K55 is a 2SK55...generally FETs.
Steve A.
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