Space Invaders player sprite randomly changes width...

[GradualGames]

I just got my Harmony cartridge in the mail and tried to load Space Invaders. Works fine, but the main player gun changes width randomly. In the Stella emulator, it remains the same width as expected.

 

I think I may have seen this happen on another cartridge, in Super Breakout, though, randomly changing the width of the paddle even when it isn't supposed to.

 

Has anyone seen anything like this happen? Is it more likely to be the harmony cartridge or maybe a dirty contact on the cartridge port, or even something starting to go bad in the TIA chip?

[Keatah]

The difficulty switches control the size. Maybe start there and work your way into the system.

[GradualGames]

The difficulty switches control the size. Maybe start there and work your way into the system.

 

Aha! That's it. The left difficulty switch appears to be faulty. If I hold it a certain way it seems to settle down. Is that something that can be replaced or fixed/cleaned fairly easily? This topic maybe doesn't belong in here, doesn't appear to actually be relevant to the harmony cartridge as I erroneously first guessed.

Edited January 1, 2018 by GradualGames

[Keatah]

Squirting a bit of contact cleaner in there might be enough to fix it. You just need to be sure the fluid gets on the contacts.

 

Or maybe it's totally worn out and needs replacing. Could be a bad solder joint on the switch, which is also easily fixed. And switches can be disassembled, too, and cleaned/inspected. So it all depends on the exact-precise cause.

Edited January 1, 2018 by Keatah