Modded 16K cartridge... what am I looking at?

[arko20]

Picked up a VIC bundle off Craigslist today, first time ever owning one of these. Came with a 16k expansion but it appears to be heavily modified, and I'm a bit of a novice when it comes to board level work. I know these came with a row of DIP switches on the board (not sure what they did to begin with, memory block maps or something) but they seem to have been re-located to stick out of the top of the cartridge, plus a new SPDT toggle switch wired in. I've tried multiple switch combinations but cannot get the system to recognize any extra memory. I realize I probably look like a moron but any help is appreciated as to what's going on here and how I can get it functional.

[srowe]

The toggle switch is probably a write protect. There looks to be some corrosion where the circuit is wired to the VR/W pin on the edge connector. Do you have a meter to trace the circuit?

[16KVIC20]

Reset button?

[Vic20-Ian]

It looks like the standard Commodore 16 K expansion with the jumper tracks broken out to a dipswitch at the top of the cartridge.

This allows the memory to be relocated to different blocks.

It can be used to load a dumped cartridge back into the correct "ROM" area of memory and then flick the switch to make it read only before starting the game with a reset.

This write protect makes the program in ram now operate like it is in rom and defeat any copy protection that might be present on bootup e.g. overwite the program at boot up.