In order to achieve true "hold button" activation, Intellitouch created a small module called a TEHMA (telephone extension hold music activator). This line-powered activator sends a signal down the phone line telling the MOH 500e unit whether or not the phone is on hold. Only phone extensions with a TEHMA can put a call on hold with the phone's hold button.
Phones without a TEHMA can put a call on hold by pressing the star key twice and then pressing the phone's hold button.
The OHP6500, 7500 and MOH 500e ship with 2 TEHMAs..
