Videoconferencing at UVa
ITS acquired an Aethra Vega X3 for one of their conference rooms. This brand of videoconference hardware (or endpoint) is the equipment of choice currently among several college and university departments in Virginia. Still, there are quirks that the user manual does not address. The following is information that has been gleaned through experience here at U.Va.
Local tests of a dual-stream session at 384 Kb (using the "Dual" or H.239 feature) between the Aethra and a Polycom PVX were successful. However, attempting the same type of connection with a site in North Carolina was not successful. Increasing the bandwidth to 768 Kb solved the problem.
Normally, a connection over a congested network behaves better at a lower bandwidth, so simple network congestion was ruled out in this case. This might have been an anomaly, but we are using 768 Kb with that site now.
Dual Mode Behavior
There is one H.239 ("dual") session possible at a time. The remote site must be connected to the Aethra before a Dual session can be initiated. If the session is not yet active, or if the remote site does not have H.239 enabled, the same unhelpful "Cannot be started" error message is displayed on the Aethra. The cause of the failure is not reported. In fact, the message may lead you to believe that the fault is with something on the Aethra end of the connection. Verify that a session is active, that a cable connecting to a signal source (like a laptop) is installed, and that the remote client has this feature enabled.
The Dual Mode feature can allow the Aethra to show a local laptop display to a remote site, or can allow a remote site to share their desktop with the Aethra. This is not a "shared application" in the T.120 sense, since control of the application cannot be delegated. It is purely for "show and tell".
When a Polycom PVX endpoint shares the view of the desktop with another endpoint such as the Aethra, the default view does not show the video windows. These can be enabled, if desired, from the menu (select the icon beside the status bar to show the menu). In fact, several combinations of video windows can be chosen, but the least obstructive to the view at the remote site is the Toolbar View with no video windows displayed. This can be altered during the session as desired.
There are two ways to use a projector with the Aethra Vega X3. One way is to use the video component out connection. The other is to use VGA out via their DVI Out connection. In our case, the DVI Out made more sense, along with using a small TV monitor for Video Out. However, the defaults would not allow the "Self" toggle on the remote to move the remote image onto the projector screen. By default, the remote image stayed on the small video monitor.
Changing the Monitor settings allowed the desired configuration. The Monitor settings can be accessed by navigating the icons:
Settings -> Audio/Video/Data -> Monitor
(Note that this location is slightly different than what the User Manual indicates.)
The "Number of Monitors" must be changed from Automatic to 2 (TV1 + High Def). The labeling would be more straightforward if it said Component + DVI, since it doesn't really matter what type of device is actually connected.
This change enables the Menu Monitor setting so that the menu can be moved. This is nice, but not truly relevant.
Put a check beside 1, then check 2 and set the menu pulldown to XGA. Set the resolution (probably 1024 x 768) but Do Not check DigitalDVI since a VGA signal is analog.
Once these settings are made, the Self button on the remote will toggle the display between the projector and the TV monitor.
Echo cancellation is enabled by default. However, the microphone still needs to be a minimum distance away from the audio speakers, and the volume needs to be adjusted to avoid over-driving the input. There is a power switch on the rear of the microphone pod.
Unlike the Polycom Viewstation, the microphone pod input signal level can be adjusted. This is a software control accessed via the menu. It should not need to be adjusted in normal use, but if the unit is moved to a very different space, this adjustment may need to be considered. To access it with the remote and menu system, go to Settings -> Audio/Video/Data -> Audio -> Pod. This interface allows adjustment of the input signal, a choice for echo cancellation (typically should be enabled), and the ability to enable/disable use of the pod.
The sound output level of the Aethra itself can be adjusted from the remote using the 3-part down/mute/up control.
Finally, the audio speakers themselves may have a power button and a volume control.
For best results, the output of the audio speakers should be set at half-volume or less. Further adjustment can then be made via the remote control. A sound level should be achieved that eliminates feedback (a ringing noise produced by interaction between the microphone and speakers). Setting any of the controls near the top of their range can produce feedback.
The ideal settings can only be deduced with some experimentation, so leave time for this activity at the beginning of a conference, or relegate it to a separate testing session.
If you experience a "ring" or feedback in your audio, even without a remote site connected, it is likely that you have inadvertantly plugged your speaker cable into the auxilliary audio input rather than the speaker output jack. They are beside each other on the back of the Aethra unit, and accept the same type of cable. Moreover, the standard clue that a cable is plugged into the wrong place -- failure to work -- does not apply because the physics of how a microphone and speaker are related lets a usable signal go to the speakers (ie, you get an audio signal) but it isn't the signal you want. Move the cable.