ATA 186 & acoustical repeaters

Unanswered Question
Jul 2nd, 2008
User Badges:

Hi, I'm trying to attach an acoustical repeaters (trillo 3 ) to an ATA 186 with CM 5.1

The call arrive correctly to the repeaters but sounds don't work (if I attach to a standard telco FXS work perfectly). I have only the led in blinking.

The producer say me that normal line put out 52V dc and 72V ac but Cisco ATA put out only 56V dc and not the ac.

Anyone have suggestion for understand this problem? Can I set some parameters on the ATA?

Thanks Enrico.

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (1 ratings)
ivillegas Tue, 07/08/2008 - 13:03
User Badges:
  • Silver, 250 points or more

The Cisco (ATA) 186 is a handset-to-Ethernet adaptor that interfaces regular analog phones with IP-based telephony networks. The ATA 186 is installed at the premises of the subscriber and supports two voice ports, each with its own independent phone number. Check the following links for more information:

pcameron Wed, 07/09/2008 - 05:59
User Badges:
  • Cisco Employee,

The specs for the ATA186 ringing signal is here -

This states that the ring signal is 40VAC RMS, so peak to peak value is 57 volts. The waveform is a modifed square wave (trapezoidal or clipped triangle wave) , not a true AC sine wave.

The LED is probably directly across the line with a capacitor to block the DC line voltage so is triggered by the AC ring signal, but the main ringer detection is not sensitive enough.

The manufacturer may be able to advise how to increase the sensitivity, otherwise it is likely you may need an external line/ring booster such as these ones -


This Discussion