Troubleshooting

ECHO IN A 321 TELECLASSROOM
An echo in the Knoxville classroom is typically caused by the audio from a speaker in the far-site classroom entering a mic at the far-site. This is either because (1) the speaker at the far-site is turned up too high and is entering a Push-to-Talk student mic, which, itself, could be potted up to high or (2) there is an open mic at the far-site. There are no adjustments that you can make to fix it. It must be taken care of at the far-site.

Hopefully, you will determine if there is an echo problem when you test the codec connection before class starts. At that time, you can tell the far-site they need to turn down their speaker, disconnect or pot down any open mics.

If an echo occurs during class, your instructor will usually say something to you. At that point, use the intercom to say, "The far-site needs to turn down their classroom speaker or their student mics". The instructor can communicate faster to the far-site than you can. You may then say, "We're calling them on the telephone now".

The telephone numbers for far-sites are listed in the control room. Also call NHE if the problem persists. The telephone number is posted above the control room telephone. A bad codec connection causes an echo immediately, and must be reconnected to stop the echo. This happens rarely.

ECHO AT FAR-SITE
This could be caused by the classroom speakers being set to loud or student mics being potted up to high. It can also be caused by the instructor standing in front of the speakers with the wireless mic.

Student mics have three different modes. During classes we use the MOM ON, momentarily on, mode. During teleconferences mics are sometimes changed to TOUCH ON /OFF mode. In this mode they will stay on until they are touched a second time. Sometimes, this can cause an echo. An off-program camera can be used to see if the red light is lit on a student mic. Pot them all down if one is, and change out the mic with another one at the break or when you get the chance.

A graphic key for the settings for the three modes is on the underside of the mics next to the white toggle switches.

CG TROUBLESHOOTING
The instructions for operating the character generator are printed above its keyboard. When the CG is selected on the preview bus and a page appears on the Preview monitor, but will not go to Program, it is usually because the PROGR ON button needs to be pushed or the CG's largest cable (which plugs into the center of the back) needs to be disconnected and then re-connected. If you can't get the page to the Preview monitor, it probably needs to be retyped. Follow the instructions to erase the page, and, if necessary, change the background and type color. Familiarize yourself with the instructions. There is a cursor on / off button and a flashing mode button on the left of the keyboard.

SWITCHER TROUBLESHOOTING
Not being able to get a source on the Preview Monitor is usually caused by someone accidentally punching in a source other than Preview on the Preview bus. The Preview bus is located below the monitors, on the left side. Sometimes, controls on the switcher have been set to unusual positions by a prior producer. The E-MEM is the quickest way to normalize the settings. Very rarely, a power board can go out on the switcher. It must be replaced by technicians.

CAMERA TROUBLESHOOTING
There are switches to the cameras under the console. Make sure they haven't been turned off accidentally by someone's foot. The CCU's are located near the control room entrance and should be checked for poor settings.

VCR TROUBLESHOOTING
DUB Group 1 VCRs can be individually turned off with the Power button. The channel should be L (for left). The speed should be SP, not SLP.