How To Read Crt Tube Part Numbers

By Author: Jestine Yong
Total Articles: 18
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All picture tubes, whether monochrome or color type are identified by a specific code consisting
of numbers and letters. The codes are different from each other because different tubes have
different characteristics.

For example, a certain monitor colour picture tube may have the designation, M34AFA63X03 that
can breakdown into 6 parts: M/34/AFA/63/X/03

Part 1: Application

Computer monitor tubes start with the letter "M while for a TV picture tube, it start with A.

Part 2: Screen diagonal measure in centimeters (cm)

The 34 means the diagonal viewing measure is a minimum of 34cm which refers to 14 tube, 36cm
is 15, 41cm is 17 and so on.

Part 3: Family code

The three letters AFA designate a family of tubes that have similar physical and electrical
characteristic. These letters are assigned alphabetically beginning with AAA, followed by AAB,
AAC etc.

Part 4: Family number

The number 63 shows a specific tube within the family code. A different number is assigned to
tubes within the same ...
... family that have different neck diameters, for example a single digit would
be a monochrome tube, but this two-digit number shows it is colour.

Part 5: Phosphor Type
The fifth symbol gives the phosphor designation. The letter X here corresponds to P22 for colour
picture tubes. Colour monitor tubes can have any other single letter (excluding I, O, or W) to
designate other phosphor type for various applications. For monochrome pictures, the phosphor
symbol is WW, corresponding to P4. Monochrome monitor tubes also can use WW or some
other two-letter combination (excluding I and O).

Part 6: Integral neck components
The sixth symbol is assigned only for tubes having integral neck components, such as the
deflection yoke. The specs are only apply to a particular tube manufacturer. The primary
consideration here is winding inductance. The yoke coils have different sensitivity i.e.
deflection per Amp in both horizontal and vertical.
About the Author Jestine Yong is a electronic repairer and a writer.For more repair information, please visit http://www.noahtec.com>