What is the first thing to check when telephones within the business have no dial tone and the EMTA is powered up?

When dealing with a situation where telephones within a business have no dial tone, it's important to check the functionality of the equipment and the system's integrity before proceeding with more drastic measures, such as replacement. Checking the dial tone from the EMTA using a telephone test set directly tests the output from the EMTA to determine if it is functioning correctly and delivering a dial tone.

Using a telephone test set allows the technician to verify if the issue lies within the EMTA itself or if it's related to the wiring or the telephones connected to it. If the test set indicates that there is a dial tone present at the EMTA, it suggests that the device is operational, directing the technician's focus to inspect the internal wiring or the telephones. Conversely, if there's no dial tone, it indicates that the problem could be with the EMTA, and further troubleshooting or replacement may then be warranted.

This choice is critical because diagnosing the problem directly from the EMTA provides immediate feedback on the operational status of the service, thus guiding further actions effectively.