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See TV in a CRT monitor without using CPU !! Help needed.

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Newbie level 4
Jan 8, 2006
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Kerala, INDIA
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Actually this is related to a more complex project(like what i done in the Van eck phreaking project). Please help to solve my problems. I am going to present it in a nicer way. You may think this as weird. Please dont give a complete alternate suggestion. Yes this is weird.

Basically I am going to use my old CRT monitor as a CRT tube only. The rest of TV circuits are going to be added to it.(Like tuner, demodulation etc..). Ok now scenario clear .....

After the received signal from the antenna I will tune it amplify it and demodulate it to get the video data.

Now I have the monitor ON with power supplied to it. The Data input to the monitor(15 pin VGA cable) is lying there hungry for input.

Now I am going to give the demodulated data to vga cable of monitor. Yes... I have impedence matched it to get it in to the corresponding voltage level of monitor. Then I fed it to the Blue input of VGA cable. Red and Green are left blank. So the display will be Blue and Black instead of Black and white.... Suppose I have grounded the signals well.... Now what is still required is sync signals. H-sync and V-sync to be fed to the corresponding pins of VGA cable.

You may think of a sync seperator from the input signal. No . I dont want that . Leave that option. I want to genearate the syncs externally. And I want a good range. 50-100 Hz for Vertical sync and 30-95KHz for H-sync. These signals will be supplied to their respective pins. Then I can see the display on the monitor. I can tune the Syncs to get perfect display.

So what I need is
1)To know whether this will work.(If this wont work, please tell how to teak this. Dont provide a complete alternative solution like RGB to VGA converter. I know that. What I need is a good range for sync tuning)
2)sync generating circuits with option for fine tuning in the specified range and volatage levels according to monitor.
3)I have a monochrome TV circuit set at hand(with option for V-Hold and H-Hold). Please tell how to tweak it to get the sync signals from it.

Thats it....

"There ain't no rules around here. We're trying to accomplish something." -- Thomas Alva Edison

Most computer monitors won't sweep much slower than 31.5 kHz horizontal and 60 Hz vertical. You need to find a computer monitor that can sweep at TV rates: 15.75 kHz horizontal, and 50 Hz or 60 Hz vertical, depending on your video standard. If your monitor doesn't sweep at those rates, then your project is dead, because you said you don't want to use any fancy video standard converter.

If the monitor also has "sync on green" (many do), then you can probably feed your composite video signal straight into the green input, and you'll see a green TV picture. If that works, feed you signal into all three inputs (with suitable buffering) for a black&white TV picture, or build a chroma decoder (like in a TV set) to get full color.

Additional problem: some computer monitors resist interlacing, and will jitter vertically or misalign the two fields.

Re: See TV in a CRT monitor without using CPU !! Help needed

try usiong the tv decoder card. go to

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