A sample business object probably wouldn't be too useful as it depends specifically on both which mainframe system and emulator (emulators normally cost money) that you need to use.
If what you're looking for is something generic to learn on, I'd recommend finding a publicly accessible IBM mainframe to try and connect to (for example pub400.com), install whatever free terminal emulator IBM is offering and then go from there. I have tried the specific combination of pub400 and IBM iAccess Client Solutions as the emulator, and it does work for learning purposes.
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James Man
Professional Services
Blue Prism
Asia/Hong_Kong
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