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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: barney on January 12, 2016, 09:40:45 PM

Title: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: barney on January 12, 2016, 09:40:45 PM

Inside my monitor, I noticed two adjustment knobs labeled "SDK" and "Screen".  Does anybody know what they are for?  Thanks.

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: Oldsmobile_Mike on January 13, 2016, 01:52:07 AM

Turn them and see?  :laughing:

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: spaceman88 on January 13, 2016, 02:18:25 AM

Quote from: barney;802000

Inside my monitor, I noticed two adjustment knobs labeled "SDK" and "Screen".  Does anybody know what they are for?  Thanks.

Is the "Screen" on the flyback transformer? If so it will basically adjust brightness, although if you go too high you will get retrace lines and your picture will look like crap. On most flybacks there is also a "focus" control. Now I haven't taken apart a 1080 in 15 years so your mileage may vary :-). Not sure about SDK.

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: RobertB on January 13, 2016, 03:18:08 AM

E-mail Ray Carlsen your question.  He has worked on the 1080 monitor.

Truly,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: Amiwest on January 13, 2016, 06:08:05 PM

http://personalpages.tds.net/~rcarlsen/cbm/monitors/1080/ -schematic
http://www.manualslib.com/manual/971285/Amiga-1080.html -user manual

Hope this helps

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: barney on January 13, 2016, 08:41:29 PM

Thanks for your help everybody.  From what the manual states, it looks like the "HDK" knob controls the focus and the "Screen" changes the brightness.  Thanks.

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: spaceman88 on January 13, 2016, 10:09:06 PM

After the picture tube ages, you can often improve your picture by adjusting the screen and focus controls.

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: barney on January 13, 2016, 11:17:48 PM

In addition the the "screen" and "HDK" controls there are also a series of other adjustment knobs on the board such as "sub tint", "sub bright", "comp sub bright", etc.  Has anybody here ever had to adjust these knobs before.

Title: Re: Commodore 1080 Monitor: What do the "HDK" and "SCREEN" adjustment dials do?
Post by: spaceman88 on January 13, 2016, 11:58:27 PM

Quote from: barney;802094

In addition the the "screen" and "HDK" controls there are also a series of other adjustment knobs on the board such as "sub tint", "sub bright", "comp sub bright", etc.  Has anybody here ever had to adjust these knobs before.

These (like the Focus and screen) are factory set and are generally only adjusted to compensate for a fading picture tube. There should also be Red, Green and Blue controls (most often on the small CRT board). If you turn down the colour adjustment on the front so that you have a B&W picture (on some monitors you need to input a composite video signal not RGB), and your screen has a green or red or blue tint you adjust the other controls to get back to a grey image,