Commodore 1701 Monitor issues, please help/diagnose?

Capitalistix

Morden's Lackey
10 Year Member
Joined
Oct 4, 2011
Posts
357
While this technically isn't an "arcade" issue, its definitely a CRT monitor issue so I hope to find some aid here in case this has happened to anyone's TV or arcade monitor. I recently purchased a Commodore 1701 monitor (for the Commodore 64 computer, still has normal AV inputs though) and it powers on just fine but when the C64 is connected (either to the luma/ chroma in back or the AV ports in front) it wants to show the normal blue Commodore BASIC screen, but its got these diagonal "tears" through the screen. Ive troubleshot a few arcade CRTs before (rejuvenating, cap kits etc.) but Ive never seen anything like this. Im wondering if anyone knows whats causing this and what I might be able to do to fix it? Any info would be greatly greatly appreciated!

Im thinking this might be a bad capacitor issue?

Heres a pic of the problem:

 

ECZangief

The Real Al Bundy
Joined
Dec 20, 2009
Posts
772
It looks like a horizontal sync issue for starters. Does is display other colors?

Edit: reread and saw that the all blue commodore screen is expected.

Looks like horizontal sync to my nubile young eyes.
 
Last edited:

Capitalistix

Morden's Lackey
10 Year Member
Joined
Oct 4, 2011
Posts
357
The service manual states problems with horizontal sync can be caused by a faulty IC in the monitor (IC501) to be exact. Could this be it? If so, does anyone know where I could locate such a specific IC?

Heres a video of turning the Vertical hold and H. Position pots, as instructed to by a member of another forum:

http://www.youtube.com/watch?v=7_tQO62LfMo&feature=youtu.be
 

Capitalistix

Morden's Lackey
10 Year Member
Joined
Oct 4, 2011
Posts
357
Okay, nevermind... I plugged the commodore's PSU into its own outlet and it works just fine now. I had previously had the C64 plugged into a power strip. Im assuming it had something to do with the C64 not getting enough power and thus sending a screwed up signal to the monitor!
 

jambitboom

Cham Cham's Banana
Joined
Mar 10, 2012
Posts
161
Okay, nevermind... I plugged the commodore's PSU into its own outlet and it works just fine now. I had previously had the C64 plugged into a power strip. Im assuming it had something to do with the C64 not getting enough power and thus sending a screwed up signal to the monitor!

It's always nice when a problem shakes itself out!
 
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