Thank you for visiting RF Cafe! Electronics World Cover,TOC,and list of posted Popular Electronics articles QST Radio & TV News Radio-Craft Radio-Electronics Short Wave Craft Wireless World About RF Cafe RF Cafe Homepage RF Cafe in Morse Code Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs Twitter LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes AN/MPN-14 Radar 5CCG Notable Quotes App Notes Calculators Education Magazines Software,T-Shirts,Coffee Mugs Articles - submitted by RF Cafe visitors Simulators Technical Writings RF Cafe Archives Test Notes Wireless System Designer RF Stencils for Visio Shapes for Word Search RF Cafe Sitemap Advertising Facebook RF Cafe Forums RF Cafe Homepage Thank you for visiting RF Cafe!

See TV in a CRT Monitor Without Using CPU !! - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues. Original posts:

Amateur Radio | Antennas | Circuits & Components | Systems | Test & Measurement


Koroth
Post subject: See TV in a CRT monitor without using CPU !! Posted: Sun Feb 19, 2006 12:35 pm

Lieutenant

Joined: Sun Feb 19, 2006 12:26 pm
Posts: 1
Actually this is related to a more complex project(like what i done in the Van eck phreaking project). Please help to solve my problem. I am going to present it in a nice 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

_________________
" Those who desire peace should prepare for war " - anonymous


Top

fred47
Post subject: CRT issuePosted: Wed Feb 22, 2006 4:12 pm

General


Joined: Wed Feb 22, 2006 3:51 pm
Posts: 104
Hi,
Broadcast and consumer video is interlaced - only alternating lines are sent each field; two fields (one with the odd-numbered lines, one with the even-numbered lines) make up one frame of 525 linesw. This interlacing allows running the horizontal scanning frequency at 1/2 the rate that would be required with non-interlaced (called "progressive") scanning. So the resolution you get from a standard VGA monitor with a horizontal frequency of 31.5 kHz is equal to the resolution you get from standard TV at 15.75 kHz horizontal frequency. The tradeoff is that motion isn't as smooth on an interlaced-scan display as on a progressive-scan display.

One issue is that many computer monitors will not work well at a 15.75 kHz scanning rate - they're just not designed for it. (So check the specification for the monitor you're using).

Generating unlocked synchronizing signals: good luck - you'll need it! If you're off by a small percentage of the scan frequencies, the picture will roll or tear. It must be exact - which is why TV receivers all have a sync separator. Oh yes, extreme stability would also be required - no VCOs here!

You might want to re-think exactly what you want.

Good Luck!



Posted  11/12/2012

RF Cafe Software

   Wireless System Designer - RF Cafe
Wireless System Designer

RF & EE Symbols Word
RF Stencils for Visio
Calculator Workbook
RF Workbench
Smith Chartâ„¢ for Visio
Smith Chartâ„¢ for Excel

About RF Cafe

Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2022
Webmaster:
Kirt Blattenberger,
 BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:
 AirplanesAndRockets.com

Try Using SEARCH
to Find What You Need. 
There are 1,000s of Pages Indexed on RF Cafe !

height-line