Technical problem help!!!

[Comet]

Hi!

I got my first VIC 20 today... Never had one before (used my brothers computer 'back then')

I should be happy.. but I'm not.

The screen is all just black & white.

The screen is allso pulled to the left..When I tried "Sargon II chess" that came with it, a part of the chessboard was outside the screen..

Is it perhaps just the RF-modulator??

Or is it the VIC-20 itself???

I got all mad and started to adjust all those adjustable pots & caps I could find inside (both Vic and modulator) but nothing seemed to help..

Does anyone have any suggestions??

Help is MOST welcome!!

Thanks
Comet

[ruud]

> Or is it the VIC-20 itself???

What is the number of the video chip? It seems you've got a NTSC-version instead of the PAL-one.

[Comet]

The videochip says: 6561-101

Today I resoldered the pinouts on the plug coming from modulator to Vic. The picture is stabile now. I also found a TINY little 'tingy' I could adjust next to the videochip, Tadaa the colours came. but no white!? what's supposed to be white is grey..

"Sargon chess" is still pulled outside the screen. But it seems the basic-screen is slightly better.

Hope this is relevant information!

Thank you

Comet

[carlsson]

The fact that white is more brown or grey is quite common, at least on RF modulated systems. Dunno about the other thing, is your TV not syncing correctly or a faulty signal?

Since you seem good at the soldering iron and already is into fiddling, have you considered connecting the composite video from VIC directly to a TV without using the RF modulator? Most TVs have composite video in, either separately or through a SCART connector. Not only may it solve your problem (although I'm not so sure about that), but it will also give you a sharper picture and better colours.

[Leeeeee]

"Sargon chess" is still pulled outside the screen.

Nothing wrong there, use the cursor keys to centre it like it says in the destructions.

Lee.

[Comet]

Hi!

Nothing wrong there, use the cursor keys to centre it like it says in the destructions.

.......I didn't have them . but yes, it worked!

The fact that white is more brown or grey is quite common, at least on RF modulated systems

Ok. I did a comparison with VICE emulator screen. guess it can't be compared... I couldnt remember anyway.. it's been over 17 years since last time

Next time I'll check things BETTER before posting!!!!!



Comet

[carlsson]

The Basic screen should be more or less centered in the picture if 1) everything is operating correctly and 2) you have the right combination of video chip and TV system.

It may be something odd like a Kernel ROM from a NTSC machine but installed in a PAL machine if the screen is stable but very much off center. It sounds weird, but you should be able to PEEK(36864), PEEK(36865) to find out the initial values. On a PAL machine they are 12 and 38, on NTSC it is 5 and 25.