We are a business telephone repair company looking to begin to repair the ESI line of telephones in addition to the other system telephones that we currently repair.
I have several questions:
Are the newer systems backwards compatible? If, fo instance, I picked up an S-Class system, could I then use it to test older ESI phones?
What models would I not be able to test if I picked up a C-Class system as opposed to the S-Class?
If the newer systems are not backwards compatible, how many different test systems would I need to be able to test all ESI phones? Which are they?
Are you ESI dealers sending many phones out for repair that are outside of the ESI warranty?
Thank you very much for your assistance!