When you are on-line with a remote system, two things should happen when you type a key on your keyboard. Your telecommunications software should send the character to the remote system, and it should display the character on your screen so you can see what you typed. However, your software also displays characters on the screen that come from the remote system. Here is the tricky part: if the remote system echoes each character back to you when you type it, you need to set your software to run in full duplex. If the remote system doesn't echo characters, set your software to half duplex.
· Tip: If you see double characters when you type at the keyboard while online with a remote system, you probably have half duplex set when you should set full duplex.