Keep the Learning BurningOn the front line in AV’s toughest environment. 7/12/2010 11:47 AM Eastern
Keep the Learning Burning
Jul 12, 2010 3:47 PM, By Bennett Liles
On the front line in AV’s toughest environment.
Nowhere do AV systems have more direct impact on the lives of more people than American colleges and universities. Hundreds of thousands of projectors, video displays, media players, and document cameras convey a daily deluge of information directly to students. The campus AV plant is a dynamic machine—a media engine with spinning disks, flashing emitters, burning lamps, and lots of amateur operators.
The campus AV technician’s mantra is minimizing class time lost to malfunctions and operator error in an environment where each room system may be run for 10 hours or more per day by dozens of different operators—most of whom, while highly educated, have had no formal training in AV technology. Classes, club meetings, and special events make maintenance access to each room very tight, and it requires that the AV tech have an up-to-the-minute schedule for each classroom, conference room, and auditorium that can be searched by day, time, room, and user.
Clayton State University has a student body of 6,000 with 101 AV-equipped rooms and one technician—that’s me. I’m the AV guy with the tweaker and the flashlight. Current remodeling and renovation will soon bring that number to 107.
The university has come a long way in AV in the past eight years. In 2002, when I arrived, there was not a single projector-equipped classroom on the campus. Now all the classrooms have permanently mounted projectors, and a mix of 71 classrooms, conference rooms, and auditoriums have AV control systems—most of which I have installed between semesters.
Being the sole AV tech person for such a campus requires a special method of operation. I often liken my job to having 101 plates spinning on sticks. You can’t let too many go wobbling or there will be broken plates everywhere, so careful planning and prevention is the key to staying on top of it. I take every opportunity, usually between semesters, during spring break, and sometimes when I’m just passing by an empty classroom, to perform a quick check—particularly in those rooms the schedule show to be the busiest. A quick check involves cleaning the projector’s air filter (which clogs fastest in carpeted rooms), checking the VGA cable for bent pins, hooking up a handheld AV test generator to the PC connections, spinning a DVD in the player, and sliding a color print onto the document camera. All these checks can be done in around 4 minutes if performed in the right order and if I don’t need a ladder to get to the projector. As I go through each room, I check off each task from a pre-printed form that I made and I enter any maintenance items from this into an Excel workbook with a separate tabbed worksheet for each room. Longer-term maintenance projects such as changing control systems or doing any rewiring are planned for the day after classes end each semester.
Installation vs. Maintenance
The three primary points of failure in classroom AV systems are VGA connectors, infrared buds attached to media players, and projector lamps. There is an entirely different mindset between AV installers and AV maintenance techs, particularly when one technician is time-stretched to keep such a large plant running, on how these items should be maintained. When the Clayton State University center and its 22 AV-equipped rooms first entered service in 2004, I went through the nice, neat contractor wiring of each podium and conference table and cut all but one of the tie-wraps around the VGA cables that connect to user PCs. I have to replace several VGA cables per week because the pins get bent out of alignment from the wear of being connected to and disconnected from instructor laptops dozens of times per day. Having only a single tie-wrap dramatically cuts down on the time needed to swap out the cables—much of which occurs either during classes or in the brief break between. In those situations, I have to operate in similar fashion to a NASCAR pit crew getting into the podium, fixing the problem, locking the access doors, and getting out of the way. Fortunately, the podiums need no fuel or tires. In rooms with no podium, such as biology labs, a short VGA cable running through the wall and up to the projectors is fastened and tie wrapped onto the end so that when the connector is damaged, only the short piece is replaced rather than having to thread an new cable all the way up to the ceiling.
The same free-cable method applies to power cords for media players. These are mostly consumer-grade VCR/DVD players, and there’s no trying to quickly fix them in the classroom. Instead, I swap out the problem unit with one from our backup inventory. For quick replacement, the power cables are kept tie-wrap-free. In some cases, where the podium requires fishing the power cable down through several compartments, I’ve made up 5ft. AC extensions for the media player so they can be AC-connected in the same podium compartment where they sit, with little clutter. A far better solution would be for them to have their own standardized AC connections right on the chassis. This would result in a lot less discarded copper when the units have to be retired. Other than malfunctions, the most common trouble with IR-linked media players is the IR extender buds getting knocked off. The adhesive they come with is not suited for the more challenging and robust academic environment, so I use plumber’s glue to attach them to the face of the player. It provides a sturdy seal, and the bud can still be removed with a firm pinch and twist without damaging the face of the player.Depending on the model, when projector lamps reach a certain number of hours, special attention is directed at those rooms, and at the first sign or report of a lamp dimming, I take action to avoid a lamp failing during a class. Occasionally, projectors have other problems and have to be replaced on short notice, which means I have to be on my toes should a projector need to be switched out. Many integrators like to thread the cables down through a mounting pipe and through the mount to provide a better-looking installation, and this does have the desired effect, but when a projector has to be changed rapidly, having cables strung through the mount slows things down and sometimes requires the projector to be held with one hand while the cables are freed with the other, all while the AV tech is standing on a ladder. To avoid this, I have drilled separate holes through the ceiling tiles near the mounting pipes and run bundled cables so that there is no contact between the cables and the mount. In some rooms, the cables are run down the outside of the black mounting pipe and secured to it with black tie wraps. Of course, I keep situations requiring projector swaps to a minimum by inspecting all classroom systems during breaks between semesters. The typical tools used on these checks are a handheld video pattern and tone generator, an AC inductive sensor, a test DVD, a printed color test pattern for the document cameras, and a can of compressed air for the projector filters.
Keep the Learning Burning
Jul 12, 2010 3:47 PM, By Bennett Liles
On the front line in AV’s toughest environment.
Keeping this AV plant up and running as one-person team would be impossible without having most of these systems on a network. Proactive operation is the key, and the enabling tool in this concept is the central monitoring and control application. All of the classroom control systems on this campus are Extron, running Global Configurator and GlobalViewer Enterprise software. I have configured each system with projector lamp out, high temp, and disconnect alarms that send automated notification emails.
On the Peachtree City, Ga., campus, 27 miles away, the control panels are on UPS power with Furman Sound MP-15 sequencers providing power to all other podium gear. The MP-15 status circuit is connected to a digital input on the Extron MLC 104 podium control panel to notify me by email when there is a power loss and when power has been restored. At that distance from my office, the more remote control and system status sensing I have, the better.
All control panels on every campus have both a daily system shutdown time and a 2-hour timeout, which turns off the controller and display after 2 hours without any manual input. During summer classes, which are longer in duration, the system timeout is extended to 3 hours. The normal and summer configurations are stored and backed up so that I can make the change with one upload to all the network host units prior to the start of summer classes. Typically, each building has one or two network host controllers. The more controllers that are designated as hosts, the longer the configuration updates take to upload. I’ve found that with the Extron system, reconfiguration is fast and simple. When an item of a different make and model is installed, I upload the configuration change first and then take the equipment to the room so that the installation can be checked while I’m there.
Some of the most useful software features in monitoring a large AV system are button stats, inventory, and logs. The button stats are useful in allocating gear to the rooms where it is most needed because they show how many times each button on the controller in a classroom has been pushed. Some document cameras will have sharper, brighter images than others. Through button stats, the AV technician can allocate the better units to the busiest rooms while units that are still fully functional but not optimal are moved to rooms where they are less frequently needed.
Under our state guidelines, any item more than $3,000 in original cost must be inventoried and accounted for annually, and the Excel inventory spreadsheet makes fast work of this with keyword searches and color coding, but it is also handy for routine resource tracking. I keep a separate Excel spreadsheet log with each classroom on its own worksheet so that I can easily pull up the history of problems and fixes for each room.
The Human Element
Around 80 percent of trouble reports and complaints arise from about 5 percent of the faculty. These complaints can be compared to logs and even realtime control panel button monitoring to determine what is happening when user error is suspected. (However, the Extron controllers have cut user error significantly.) It is supremely frustrating for an instructor with a tightly scheduled series of lesson plans to have trouble operating the AV control system, and this is particularly vexing when the problem is due to equipment malfunctions. Since most of the calls I get involve operator error, these tend to drop off sharply after the second week or so of each semester. Most of the calls come from adjunct faculty not familiar with the control systems or from attempts to play bad discs in the media players. The great majority of faculty members react with patience, and they tend to learn what they need to know quickly.
In the week prior to fall semester, there are a series of brief AV orientation sessions for new faculty, all of whom are issued laptop computers by the university. Among the topics covered are the key combinations for switching PC display modes, visual checks of VGA connectors prior to using them, and a few other simple points. These sessions cut user error calls dramatically for those who attend, and it is time well-invested. There are always a few technophobes that still prefer a TV set rather than the classroom AV system, but most instructors take to the AV systems very easily. Operational difficulties can be embarrassing for professors during a class, so I also offer private, individual training in the same classroom at a time when the room is empty. A professor’s embarrassment can quickly turn to anger, so even when a trudge across campus results in simply turning up a volume knob, I don’t advertise the problem, or lack of one, to the class.
A good working relationship with the IT staff is critical. Their assistance goes beyond just providing IP addresses for AV controllers. Some of my remote indications such as power loss and podium access door removal can benefit them since they sometimes have hardware such as wireless access points inside the podiums. Conversely, they help with any router or network line trouble that affects my communication with AV controllers.
In maintaining such an educational AV operation, time is an enemy that has to be headed off at every pass. The leverage needed to stay on top of it is provided by careful planning and proactive methods enabled largely by centralized network monitoring and control. That teamwork and coordination combine to keep all the plates spinning.