Audio Visual:

Trouble Shoot VCR's, TV's, Overhead Projectors and related AV equipment

AUDIO RECORDER & CASSETTE DECKS

OVERHEAD PROJECTORS

16mm PROJECTOR

CAMCORDER

Television Troubleshooting Guide
 

1. Unplug the unit before making any electrical checks.!!!!!!!!!!!!!!!!

2. If the unit is dead ( no lights on the front panel or on-off indicator light not lit) check the A/C cord for exposed or broken wire. Check the plug itself for broken connectors. If the A/C cord is not in good shape stop and send the unit in for A/C cord replacement. Do not attempt to use the unit with a bad A/C cord it will cause bodily harm to you or someone else.

3. If the A/C cord is in good shape try plugging the unit into another known good A/C outlet. If it still doesn't operate send the unit in to be repaired.

4. There is not much that you can do for your TV except keep it as dust free as possible. This I know is an oxymoron since most of the T.V.'s are mounted on the ceiling . TV's are electromagnetic and they work like a sponge when it comes to dust. The problem with dust is that it blankets the printed circuit board with a layer of dirt which counteracts air flow needed to cool the components. Each TV that we receive for repair or service is air blown to get rid of dust and mineral deposits that rob the life expectancy of your unit.

5. On some of the newer units the microprocessors will lock-up and cause the unit to shut down or not function at all. You may notice the timer light blinking on the front , but the TV won't turn on. A quick fix could be to unplug the unit for 15 to 20 minutes, re-plug the unit into a know good A/C outlet. This has worked on several TV's in the past. If the unit still fails to operate then submit a work order to have the TV serviced..

7. A quick guide in checking for a snowy picture is to use a good video source. You can use a good VCR and playback a pre-recorded tape, ( like a movie or rental tape), and if you get a good picture then you know the problem is not the TV. You can use other video sources like, a camcorder, CD video player, or any type of NTSC signal source that can be hooked into the back of your set. The object is to eliminate bad video sources, cable problems and connectors. All can degrade your video signal to a snowy picture. After checking all of these options and you still have a snowy picture call for service.

8. Bad sound is caused by several different problems. I have found all kinds of objects stuck into speakers. First look for objects that may be stuck in the speaker. Examine the front speaker grill for odd sized holes that may look like someone might have pushed something through it . If you do discover a hole or something stuck in the speaker call for service. If your T.V is attached to a VCR or some other video source other than an antenna (disconnect all other connections) use only the antenna or cable source. Turn the unit back on and check the sound on a good channel. If the sound is bad or distorted then send the unit to service. If your sound returns, connect each unit up separately until the sound is distorted again. that unit or the connectors is the problem. Make sure your connecting cable(s) are not causing failure. Also keep in mind that if you have a TV that is 15" or smaller and the sound is bad in your class room. It is the small speakers that they use in the smaller sets, that were designed for bedrooms and kitchens not classrooms.

9. As most of you know, your TV will not retain memory after its unplugged from the wall. Each time you disconnect your TV from an A/C source you will lose your programming and you will have to use a remote control to regain memory and auto channel. 

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Back To Equipment List 

OVERHEAD PROJECTOR
 

1. UNPLUG THE UNIT BEFORE MAKING ANY OPERATIONAL CHECKS.

2. If the unit fails to operate (no fan or light), check the A/C power cord and plug for any exposed, broken or missing connectors or wires. If A/C cord or plug shows any of these problems, "STOP", and submit a work order.

3. If the power cord and plug appear OK, try plugging into another A/C power outlet, making sure the motor switch is in the off position. If unit still fails, submit a work order for repair.

4. If the LAMP fails to light, but the fan works. (UNPLUG THE UNIT) Check projector lamp to insure lamp is seated all the way into the socket and that the socket is not broken. Also, check that the lamp is good by replacing it with a new bulb, if not replace with manufacture's recommended replacement. Use caution when transporting overhead projectors, carry them by their base and avoid "jerky" movements that can cause the bulbs to fail.

5. If the FAN fails to operate "STOP" (UNPLUG, DO NOT OPERATE THE UNIT WITHOUT A FAN). Look at the fan assembly for any foreign objects that may be lodged in the fan. If possible remove obstruction and restart. Should fan still fail to operate submit a request for repair.

6. Most units contain a safety cutoff switch which is either the lid or door. This assembly must be fully engaged to ensure operation of unit.

7. Some units have a dual lamp switch. If not fully engaged it will cast shadows on the image. Make sure switch is in either primary or back-up position.

8. Dust and fingerprints on the lens will reduce the brightness of the image and will cause it to appear dull or low in contrast. Using a lintless cloth wipe front and rear of all lens. CAUTION: HANDLE ONLY WHEN COOL. REMOVE ALL FINGERPRINTS FROM GLASS SURFACES. Also insure that proper type lamp is being used.

9. The projection lens mirrors (fresnel lens) are NOT to be cleaned with a cloth or lens cleaner. Remove any surface dirt on these mirrors with a soft brush or compressed air.

10. Periodic maintenance is required, including cleaning and occasional replacement of some parts. We recommend that you service your equipment at least once a year so that it remains in first-class operating condition.


PROJECTION-LAMP TIPS

• Rough treatment of the projector may damage the projection lamp.
• Turn projector off when finished.
• Unplug the power cord before servicing the unit.
• Allow for unrestricted flow of air to the exhaust (min. 1 foot).
• Always wipe fingerprints from all glass surfaces.
• Do not move unit when hot.

16 MM PROJECTOR


 

1. UNPLUG THE UNIT BEFORE MAKING ANY OPERATIONAL CHECKS

2. If unit fails to operate check the A/C power cord for any exposed or broken wires. Check the plug for any broken or loose connectors. If A/C cord or plug shows any of these problems, STOP, send unit to be recycled.

3. If the A/C cord and plug appear OK, try plugging unit into another A/C outlet. Make sure motor switch is in the forward position. If unit still fails to function, send to the Tech Department for recycling.

4. If your film does not thread automatically push auto load #2 forward. Check film leader. Is it trimmed properly? Make sure exciter lamp cover is firmly in place and the film threading path is free of obstructions. Also check that the run /still control is in the run position.

5. If Exciter lamp lights but there is no sound ,check to see that film is properly threaded, is the volume turned up, are there obstructions in loading path?

6. If Exciter or Projection lamp fails to light, (UNPLUG THE UNIT). Check to see if the lamp is good and the proper lamp is being used. If lamp is bad, replace with manufactures recommended replacement. If unknown, try using Google to search for your projectors manufactuar or model.

7. If your sound volume is not adequate ( fuzzy/garbled ), check volume control. Is it high enough? Is tone control set properly? Visually check that the film is tight around the sound drum and that the exciter lamp filament is not damaged. Also ensure that the external speaker(s) are at 4 Ohm minimum load.

8. Cleaning of the film path should be done with a soft cloth or brush which has been moistened with any naphtha-based agent (lighter fluid). CAUTION: PROJECTOR AND LAMP MUST BE TURNED OFF AND COOLED DOWN BEFORE CLEANING. Gently clean and remove any loose particles, accumulated dirt or emulsions.

9. Periodic maintenance is required including cleaning and occasional replacement of some parts. We recommend that you service your equipment at least once a year so that it remains in first-class operating condition.


PROJECTION-LAMP TIPS
• Rough treatment of the projector may damage the projection lamp.
• Turn projector off when finished.
• Unplug the power cord before servicing the unit.
• Allow for unrestricted flow of air to the exhaust.
• Always wipe fingerprints from all glass surfaces.
• Do not move projector when hot .