TROUBLESHOOTING
VORTEX EF2201 Reference Manual 22 Technical Support: 800.932.2774
T
ROUBLESHOOTING
R
ESIDUAL
 E
CHO
If there is residual echo in the system, it may not be a problem with the EF2201.  
There are different types of echoes that come from different directions, and the 
EF2201 is only designed to remove one of them.  The first step is to make sure the 
echo isn’t caused by something else.  Then, the EF2201 can be adjusted to remove 
any residual echo coming from the hybrid.
Identifying the Echo 
Source
If the system has both audio and video conferencing, troubleshoot the system without 
the EF2201 at first.  This will make sure the 4-wire AECs on both ends are working 
properly.  If one side hears echo, there is a problem with the AEC on the other side.  
Troubleshoot the AEC according to the instructions for that device.
Make a call to test the EF2201’s telephone interface.  If the party on the phone hears 
echo, it is coming from the local or remote end.  Disconnect one end at a time (by 
briefly unplugging the speaker or microphone) and see when the echo goes away.  
Troubleshoot the AEC on the side (local or remote) that was causing the echo.
If residual echo is heard on the local end, try disconnecting the remote end.  If the 
echo is still there, it is coming from the EF2201.  Troubleshoot the EF2201 as 
described in the next section.  If the echo goes away when the remote end is discon-
nected, troubleshoot the AEC on the remote end.
If residual echo is heard on the remote end, disconnect the microphone(s) in the local 
room.  If the echo is still there, it is coming from the EF2201.  Troubleshoot the 
EF2201 as described below.  If the echo goes away when the microphone is discon-
nected, the echo is coming from the local room.  Troubleshoot the local AEC.
Removing the Echo If the EF2201 is not removing hybrid echo, it may be due to a mismatch of levels 
coming into the EF2201.  If levels are too far off, it may be difficult for the EF2201 to 
determine when to adapt its filter.  Make sure the levels are in the correct range by 
watching the front panel LED meters during normal conversation.  The signals should 
regularly be hitting the first yellow light, and occasionally flicker the second yellow 
light.  Adjust the incoming signal levels if necessary.  Also, make sure the Line Echo 
Cancellation feature is enabled.
C
AN
’
T
 R
ECEIVE
 C
ALLS
 
OR
 D
IAL
 O
UT
If you can’t receive calls or dial out, it could be because the telephone line is from a 
digital PBX system, or the remote control system is not properly connected.
Test with an Analog 
Phone
Try connecting a regular analog telephone to the EF2201’s line, and make a call.  If 
the telephone will not work on that line, it is probably a digital PBX line from an 
office system.  The EF2201 needs a standard analog line.  You will need to get an 
analog phone line installed for the EF2201.