Picture Tube

Television 1 Jess Role @ UEAB

Picture Tube


Other names

• CRT cathode ray tube• Screen• Picture tube• Picture bulb



Materials used

• Glass• Phosphor• Stainless plate• Steel • Iron• Tungsten• Aluminum



Television Phosphor number designation

• P 22 designated for color• P 4 for black and white• P 7 greenish-yellow light output• P 1 CRT for oscilloscope• P 11 for photographic

application that emit blue light


Worldwide type designation system (WTDS)

• Type A – for television• Type M – monitor• AAA-DZZ designation for US tubes• EAA-HZZ – European tubes• JAA-MZZ – Japanese Tubes• X – represent a color picture tube

example of WTDS A6AAAOOX


Picture tube length and deflection Angle

• Length 9 – 25 inches• 50- 114 degrees deflection angle• 105 degrees horizontal deflection

angle



Picture tube bases


Picture tube parts



Electrostatic focus


Picture tube PS


Flat picture tube


Porta TV




Gun Arrangement




















Problem and Symptoms

• Low picture clarity• No picture filament light ok high

voltage ok• Picture tube face turn to white• Black spot on the middle of the

picture tube• Low phosphor• Blurred picture


Tube testing

• Isolation technique • Picture tube tester• Variable Filament voltage supply• Observation and analysis• Second opinion


Picture Tube Replacement

• Cost effectiveness• Availability • Substitution (use tube manual)• Picture tube size• Brand• Model number or serial numbers• Structure and mounting• Make or production code



Documents

Picture Tube