How to Read CRT Tube Part Numbers

Written by Jestine Yong

Continued from page 1

Part 5: Phosphor Type The fifth symbol givesrepparttar 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,repparttar 138982 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 asrepparttar 138983 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.

Jestine Yong is a electronic repairer and a writer.For more repair information, please visit>

Understanding Transistor Data and Replacement

Written by Jestine Yong

Continued from page 1

Gain (hFE) The replacement should have a gain equal to or better thanrepparttar original and it should be as close torepparttar 138981 original specification as possible.

Gain-bandwidth (fT) repparttar 138982 replacement should have a transition frequency equal to or faster thanrepparttar 138983 original and it should be as close torepparttar 138984 original specification as possible.

Below is a table of application requirement and important specification that you can use for guidelines when comes to transistor substitution.

Application Requirement and Important Specifications 1. General purpose low level amplifier and switching transistors. Spec- hFE, IC (max), fT, VCEO 2. Power switching applications. Spec- VCEO, VCBO, hFE, IC (max), PD (max) 3. Low level IF/RF amplification. Spec- IC (max), fT, VCEO 4. Audio amplification. Spec- IC (max), PD (max), hFE, VCEO 5. High voltage transistors. Spec- VCEO, VCBO, IC (max), fT

Remember,repparttar 138985 replacement transistor should not run hot and if problem still persist, try another replacement number or getrepparttar 138986 original number if possible. Do not overlook thatrepparttar 138987 surrounding components also may causedrepparttar 138988 transistor to run hot even if original number is used.

Jestine Yong is a electronic repairer and a writer. For more repair information, please visit

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