Path: utzoo!utgpu!watserv1!watmath!maytag!watcsc!zr1 From: zr1@watcsc.waterloo.edu (Christopher Koziol) Newsgroups: comp.sys.apple2 Subject: Re: Monitor as a TV Summary: Using monitor as a TV Keywords: Mhz Message-ID: <1990Apr14.024759.13149@watcsc.waterloo.edu> Date: 14 Apr 90 02:47:59 GMT Expires: when hell freezes over References: <2550@husc6.harvard.edu> Sender: zr1@watcsc.waterloo.edu Followup-To: Eric Hsu Distribution: na Organization: Computer Science Club, University of Waterloo Lines: 64 In article <2550@husc6.harvard.edu>, ehsu@husc4.harvard.edu (Eric Hsu) wrote: > > I remember reading a long time ago about a gizmo you could attach >to your monitor and turn it into a TV. It claimed that since the monitor >actually had higher resolution than normal TVs the picture quality would be >better than TV. Does anyone know anything about this? A few years back TAXAN made a TV to RGB converter for their monitors, they only sold it for a few years, so it could not have been a big hit. > It doesn't seem too implausible. How much extra hardware would this >require? After all with a monitor and (admittedly low-fi) speaker, all you'd > I eagerly await response from those better informed than I ! > >Eric Hsu ehsu@husc4.Bitnet, ehsu@husc4.harvard.edu Television is broadcast in North America in NTSC format, the other formats are called PAL in the UK, SECAM in France, and these systems are used in different countries. NTSC broadcasts enough picture signal to produce a picture quality of 420 horizontal dots and 525 lines, while PAL has 625 lines (100 extra lines does make a difference). So most TV are really overpriced cheap monitors, and some don't even produce 525 lines, but only 230 lines, and some VCRs only record 230 or 240 lines, while SVHS can record 400 lines of signal, but if you have a a cheap TV you can't see them. Most high quality monitors have high resolution numbers, as high as 1024 X 1024 pixels. Showing a TV signal on a hi-res monitor has no effect because NTSC is only a 6 Mhz signal, but most monitors require a video signal of 15 - 30 Mhz, and monitors and TV have a picture aspect ratio of 4:3. HDTV is a different system having a picture ratio of 5 1/3:3 more like 35 mm film in theatres. HDTV aslo requires a picture of 20 Mhz to produce its 1024 scan lines, this is why it is not a standard. New TV system proposed would use a computer in the TV to double each scan line while using the NTSC format. Some are even trying to quadruple each scan line. Only the future will tell. To get the best picture you can get is to use a VCR and to use the VIDEO OUT signal to a VIDEO IN on the TV, using video signal gives a crisp picture because each time you convert the picture you lose quality, a raw video signal is the best. Also MAKE SURE your TV can show 525 scan lines, you may have to check the manual to know for sure. Some manufactures advertise higher quality picture quality, but haven't personally investigated this claim. You may not even have to buy a TV just a high quality monitor that takes NTSC raw video in, also called composite video. Using a VCR or a cable converter that has composite video out jacks. Christopher Koziol zr1@watcsc.waterloo.edu University of Waterloo Computer Science Club. Witty saying: "If I wanted your opinion, I would have given it to you! "If I wanted your opinion, I would have given it to you!"