I can't see or hear anything

Can you use the menu buttons on the TV to navigate to the control panel to automatically or manually add channels? That would be a start to make channel 3 exist again.

Check the speaker/s first. If found OK; check and replace the damaged component/s at its audio output section circuit board. If needy, replace this board as card basis. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" or "Magazine" will make surf easy. Surf the site with patience. Pull up older posts. Surf the site with patience.
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Most of these TVs show a blank screen unless they are receiving a sinal?

what are you trying to do? to hook up the tv you can use the cable output from the charter box into cable input into the tv (meaning cable as in coax cable) otherwise you can use the colored ones. red white an yellow are rca jacks but the 5 wire you talking about are prob compondent cables which are red green and blue. connect those to the tv and the other red and white ones are for audio to the tv you may have to set the charter box to select which output you are using and the tv to the right input for the rca it will prob be input 1 for the component it will be component 1
let me know if thats what you needed

The white, yellow, and red RCA phono jacks on the back are called VGA inputs and outputs. The Red is
right channel audio, The white is for left channel audio. The yellow is the video. Look carefully on the back of the unit and the input jacks and output jacks should be clearly marked.

There are several other input/output ports. One is HDMI which is flat and wide. Another, not common, is composite video which uses the three above mentioned RCA jacks as indicated plus two more colored jacks. This combination gives a better picture.

A third option is a screwed on cable for input and output. This is called a "F" connector and is only used if the receiver equipment has a built in tuner. The output of a cable box is usually an "F" connector and the above described outputs

If you connect the cable box to the DVD player input and the DVD player output to the TV input, you often must have the DVD player turned on so the signal will feed to the TV.

If the TV has multiple inputs, it is best to connect the cable box to one of the TV inputs and the DVD player to another TV input. Using the TV remote you can chose which input you want to watch. The remote should have a button labeled "input"

U get a channel numder and menu screen do show up?Not the tv,it the incomming broadcasting signal cable plug in or the cable box itself have problems.Tries unplug,replug the tv and the cable box back in like about an hour later.The tv will reset itself to the factory setting and the cable box should upgraded it softwares.Should work now.If have the same problems,tell the cable company change the cable box or check the incomming broadcasting cable wire with another tv,see the incomming broadcasting signal cable wire,with a new cable box,see if it work.

Hello,
Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} You need to upgrade to the high definition cable box---but first try this. Hook the cable from the wall directly to the tv and autoprogram it. If Comcast is anything like charter they transmit the local Hd channels in a format that digital tuner will pick them up. Just channel up/down and check out the channels with -1 and -2's behind them. Depending on where you are----your local channels will usually show up wherever they normally do but with a -1 behind it.

EX: local Fox channel on 47---autoprogram and check 47-1

If this is enough HD for you then get a two way spitter and hook your box back up and keep using the RCA (composite) cables for the best it can produce.

hope this will help..

CHARTER BOX
3 CABLES
YELLOW - VIDEO
RED - R. AUDIO CHANNEL
WHITE - LEFT AUDIO CHANNEL

Hook them up to tv's INPUT of the same colors

Then turn tv to input or av channel.

When this happens and you just see the input label try to press the power button on the front of the cable box and see if it brings the picture up. If this does produce the picture then it is a good possibility that something is interfering with the remote communicating with the cable box. I don't know if you have it contained in an entertainment center or how you have placed your equipment but if there is glass try to clean it and also wipe down the front of the cable box and make sure there is an unobstructed view of the front of the cable box.
Good Luck.

your tv is too old buy a new one,that comes cable ready less expense,good luck