Analog you can use any of the Harris Test Sets. For Merdian digital phones I do not believe that they make one, if they do it would cost around $500, and I would advise against buying one no matter what the cost, since you can use the digital phone to test the line. The other issue is that there are at least 10 different models of Meridian Modular Terminals (phones), and if there was a test set for digital phones it would have to be able to cover all of those choices otherwise it would be useless. What would happen if Nortel changed phones next year, your $500 test set might be useless.