G.fast EMI Suppressor Dongle

Model: SA-2255-GF01


The Comtest G.fast EMI Suppressor is a Common Mode EMI Filter designed and specifically built for G.fast (212Mhz). This dongle will reduce or eliminate the effects of EMI on G.fast services.

Differential signaling is used in telecommunication utilizing twisted pairs. One of the main advantages of differential signaling is increased resistance to electromagnetic noise. Resistance to electromagnetic noise is achieved only if twisted pairs are well balanced. Unfortunately, in the real world, twisted pairs are not perfectly balanced. As a result, interfering signals on Tip and Ring are not the same in amplitude and phase. Coupled signals on Tip and Ring will not be cancelled. And therefore, electromagnetic noise (EMI) has a detrimental effect on G.fast lines, reducing the usable bins and creates errors.

This Comtest G.fast EMI Suppressor will reduce or eliminate this noise and provides insertion loss of 30dB of couple signals (Electromagnetic interference signals) without adversely affecting the G.fast signal.


  • Can cure chronic trouble issues cause by EMI
  • Compatible to 212Mhz
  • Improved data rates on G.fast service



22.8mm(H) x 24.7mm(W) x 71mm(D) (0.90” x 0.97” x 2.80”)

Operating Temperature

-40 to +65 °C 

-40 to +149 °F


20g (0.7lbs)

Communications Interface

1 RJ11 Receptacle. In from wall plate/base cord; 1 RJ11 Plug. Out to Modem


1 G.fast line per unit


Compliant to CSA/UL Standards

Ordering information

Order number



G.fast EMI Suppressor Dongle