Dead Television Set.

A dead television set is one in which there is no sound
no picture and no raster nothing works.The most likley cause
of a dead set is some form of power supply ailure.Like wise
it is a good idea to check the line voltage.The cause might
be some thing entirely outside the set,such as a blown fuse
a use in the set may also be blown.I external power is
coming to the set then there may be a B+power supply failure .

Picture No Sound.

If the picture is alright but there is no sound,the trouble is in the sound section of the receiver.If the set is of the intercarrier type I-f trouble is unlikley and the trouble will usually be found in the sound detector or ampliier circuits. If seprate channel i-f's are used, the sound i-f must be checked.

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Sound, Raster No Picture

Once again your irst application of effect-to cause reasoning will depend upon whether your set is o the intercarrier type or of the seperate channel i-f type. If the set is of the intercarrier type, the existence of sound indicates there is no trouble in the i-f section
and the raster eliminates the possibility of trouble in the sweep circuits of the picture tube.
So the most likley place to look or trouble would be in the video detector And ampliier section. If the set is of the seperate channel type,the trouble could be in the picture i-f section as well as the video detector and amplifier.

Raster, No Sound NoPicture.

The absence of both sound and picture,but the existence o raster
,shows that the trouble is probably lies in the tuner
or if- sections of the set if it is of the intercarrier type.
If it is of the separate channel type the most likley place or trouble
to occur will be in the tuner or any of the if- sections common to both sound and picture.

Distorted Picture or Raster.

The most requent cause o picture distortion will be found in the sync sweep circuits.However if the frequency response of the video section if it is poor may cause some picture distortion. Picture distortion may also result from incorrect adjustment of controls or components on the picture tube neck. for more information:Collectors, hobbyists, researchers, educators, inventors...browse our library o over 1,000 science & technology inormational CDs about virtually everything under the sun!

Distorted Sound.

Sound distortion may be trace to ailure in the audiosection of the receiver. Adjustment of the tuner may cause hum in the sound and should be checked in the event that hum exist. Likewise, i the tuner is not properly adjusted sound bars may appear in the picture.

Probablity of failure.

There are some characteristics o electronics circuits that may be of help
in dertimining the most likley cause of failure. After careful analysis (1)check the suspected part by substitution.
(2)Check the capacitors in particular the paper type. Paper capacitors ail due to heat and moisture.
(3)failure of resistors. Resistors may burn out or may change value

Identiying the section of a computer.The keyboard is the primary means of direct manual input to most modern computers. The Video Display. One very common means nopermanent output is the video display. The Video display circuitry consist of three main circuit. The Timing Circuitry. This consist of a series of digiftal frequency which cfontrol the timing of the character grnerator. The Character Generator. This section perorms the task of converting the coded data into a form that can be displayed on the video monitor. The Video Display Memory. This is a special area of read/write memory (RAM)that is used to hold the character data or the video display. RAM , or Random-Access Memory, is the read/write memory used to store user programs, data, etc, RAM must work properly or the computer won't run. ROM Read-Only Memory when the computer is turn on it will automatically begifn executing programs rom ROM. Everything that the computer is able to do is determined initially by the program supplied in ROM. The CPU the central processing unit. combines the cfontrol section and the arithmetic logifc umit. Called a microprocessor. It is the (CPU) that etches and executes successive instructions rom memory (either RAM or ROM). The Power Supply. Without the power supply nothing in the computer will operates. Peripheral Intera- ces. Peripheral devices such as cassette, printers and disk drives are not really part o the computer itsel, any problem with them must be handled seperately.

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