Almost every coin handling device has a hopper inside. In a slot, it's usually in the bottom of the machine. Troubleshooting casino slot machines can be tricky, but if it's a mere coin dispensing issue, it might just mean you're running low on coins. This video will show you how to fill the slot machine hopper, and it's best to use about 200 coins— at least. It's just a basket that holds the tokens, so when someone wins, the machine will dispense them.