If you have one of the original playstation's (don't know the model number
but it actually has the A/V ports in the back so you can use standard A/V cables to connect it to your TV (it will either be mono or stereo depending on what model you have)) Anyway if the model i've described is yours you just need to tape something on top of the "door sensor" and right when it gets to the black Playstation screen you can swap discs, or if you don't like that because it's still spinning try this:
1. With power off open lid, insert REAL psx game
2. power on PSX with lid open
3. go to the CD player option and once inside that tape something over the door sensor
4. when the disc stops spinning and the number of audio tracks are visible on the screen then take out the original psx game and replace it with your back up or import
5. simply exit the CD player and the game will boot up
If you have the next model after these early playstations it doesn't have the direct A/V plugs right in the back but it does still have the parallel port, you can get something like an action replay/external mod chip for this and thats probably the cheapest/easiest way to play your backups
If you have the next model after that one you don't have the A/V plugs AND you don't have the parallel port for this you need an internal mod or I RECOMMEND the ps-x-change which someone has already stated. For this model (and all previous models) ps-x-change v1 AND v2 work.
If you have the new mini-PSOne then you need either an internal mod or the ps-x-change
VERSION 2
And that's that :
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