Download a manual for the NEC Dterm Series 80 at ManualsLib.com or ManualGuru.com. These websites each list the NEC DTerm Series 80 Telephone User Guide, in PDF format, which you can download to your computer free of charge.
At ManualsLib.com, type "NEC DTerm Series 80" in the search box on the main page, and then click the Search button to display the manual in your browser. This manual includes instructions on phone usage and programming, as well as a step-by-step guide on setting up your voice mailbox. To download the manual, click the green Download button near the top of the page, type the Captcha code, click the Get Manual button, and then click Download PDF.
At ManualGuru.com, type "NEC DTerm Series 80" in the search box near the top of main page, and then click the search icon to display a manual listing. Click the listing near the top of the page, titled "NEC DTerm Series 80 PDF Owner's Manual Download and Preview," to display the manual in your browser. To save the manual on your computer, click the blue Download button near the bottom of the page, type the Captcha code, and then click the Get Manual button. Click the blue Click to Download link to display the manual in PDF format, and then save the file on your computer.