>>>>> "NW" == Nicolas Welte <email@example.com> writes: NW> I wonder if it has something to do with the different output NW> levels of the two video pins on different versions of the VIC-20. NW> I think I found the old VIC-20 version to have dark white when I NW> use the normal video cable from a 64 that takes video from pin 4. NW> I ended up to adjust the video level with those internals pots to NW> show a bright white, maybe bright grey, so I have good contrast in NW> the picture. I'd really like to know what it really should look NW> like ... Hey, this is exactly the problem that I have -- and it's what's keeping me from taping VVV and VIMM... If I use the 5-pin C64 video cable I get a pretty sharp image, but colours are dark and washed out. The white background is more like colour 15 or 12 on the VIC-II. If I use the RF box I get a slightly brighter but much grainier image. Raymond Carlsen said on comp.sys.cbm: Ray> I've seen failing VIC chips in the C64 do that. The VIC chip in Ray> the USA version of the VIC20 is UAB7, a 6560 (the PAL version may Ray> use a different number). Before replacing the chip, I would check Ray> or change Q1, an NPN transistor used as a buffer to the video Ray> output. Any small signal NPN should work in that application. And Nicolas Welte suggested: NW> You could try to adjust the video signal level with the internal NW> pots in the VIC20. They're near the VIC chip, there's one of them NW> for the small VIC20CR board and two for the large original VIC20 NW> board. Don't touch the adjustable capacitor in the clock circuit NW> that is very close to the other adjustments. Especially with a NW> metal screwdriver it's not easy to adjust it. Haven't had the time to try either, but it might be worth a shot. I was about to buy a second VIC-20 to have something to compare with, but the seller screwed up. Royally. Still a bit pissed off :/ -- ___ . . . . . + . . o _|___|_ + . + . + . . Per Olofsson, konstnär o-o . . . o + MagerValp@cling.gu.se - + + . http://www.cling.gu.se/~cl3polof/ - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail firstname.lastname@example.org.
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