C64 and display problems

8-bit Commodore machines
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ThisGuy01
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C64 and display problems

Post by ThisGuy01 »

What could be the reason:

with the luma signal: "the screen jumps 3 points vertically (such interlace but 3 points) - the lower frame is thin (the height of the text line, then it is not black, but the whole screen is stretched so that the lower frame is about 8-9 points)

after connecting the chrome:

the image quality deteriorates even more and you can see such colors as in a noisy photo from a digital camera.


Could it be the VIC 8565?
I connect it on the low side, not through the modulator


soft comes: sprites, etc., scrolling, etc.


here is a diagram (there is no modulator diagram, which can also be damaged and introduce interference)
I do not have an oscilloscope to watch the signals, maybe someone will intuitively throw a few possible damage and a method of diagnosis.
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Kilord
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C64 and display problems

Post by Kilord »


and the TV is samajama brand LCD.
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Miwod
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C64 and display problems

Post by Miwod »


VGA monitor via SV or composite signal converter
Atari flashes on it and there is a picture of "razor"

I checked both SV and composite
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Iwa
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C64 and display problems

Post by Iwa »


Thanks jelly!

I haven't solved the problem yet.

The 300 Ohm resistor in Chroma does not affect jumping as I only connect the luminations, to be honest it does not affect the color too much.

I think something is broken on the way from the VIC to the DIN8 connector in the combo.

I was thinking about cutting the transistor - what you wrote in the topic from the link, just write that so that I do not cut them all.

Maybe on Monday I will post a video and photos from the rehearsals, it will be a more precise puzzle. With my screen, these photos from the links are a fairy tale - I would not correct anything if it were so, at least not right away.



Have a good weekend!
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Donotreadtis
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C64 and display problems

Post by Donotreadtis »


I have a question, if my mouse does not work, do you fuck up the laptop port?
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HelloThereAll
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C64 and display problems

Post by HelloThereAll »


no, I'm replacing the battery, I have a wireless mouse
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Catladyiscrazy
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C64 and display problems

Post by Catladyiscrazy »


then you probably didn't think about replacing the Chinese toy.
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Doggeboy0A
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C64 and display problems

Post by Doggeboy0A »


if it is the fault of this converter, I do not have another monitor (except 6 VGA LCD and 1 CRT - through this box) to connect to the C64 and if it turns out that the computer is OK, I will try to match the signals. The Chinese toy goes with the Pegasus and the Atari and the Manta DVD player, why should the C64 be any different?


Do you think the Luminance from the C64 has too much signal and therefore confuses the vertical sync?
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NamelessOne
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C64 and display problems

Post by NamelessOne »


You were right, the Chinese box sucks.
It goes well with NTSC signals then there is a single point interlace, PAL looks terrible. The transition from 50Hz (video) to 60Hz (VGA) also generates moving horizontal stripes.
thanks for the clue and sorry for the confusion.
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