If you have voicemail on a landline telephone, you may have a problem. Do you obsessively pick up the phone to see if a message is pending? Yet phones that properly support a nice bright voicemail indicator are rare and hard to find. This guide will help you sort it out.
The core of the problem is there are at least four different methods used to notify a phone that messages are waiting:
- Stutter Dial Tone
- 90 Volt / 90 V / 90VDC
- 24 Volt / 24 V / 24VDC
Often you're left to sort out if a particular phone with message waiting will work with your particular message system. Worse yet, some carriers rename the features, for example referring to FSK as "Illuminated Message Waiting", visual message waiting indicator (VMWI), or something entirely different.
This guide covers products known to work for message waiting indication, to help you find a product that matches your voicemail provider.
Which carriers use which system?
- Vonage: FSK
- Most PABX systems: 90V
- Others? Please add them if you know...
Won't my caller ID unit do this?
Some caller ID systems will tell you how many times the phone has rung, but not the voicemail status. Others will "pick up" the phone to detect a stutter dialtone, leading to a potential loss of an incoming call. Your best bet is a FSK style message light, if supported by your voicemail provider.