randy@ranhome.UUCP (Randy Horton) (06/21/86)
I remember once seeing advertised somewhere a converter which would convert RGB video to composite video. At that time I had no need of such a device, so I didn't pay much attention to it. However, now I have a compatible with a color graphics card. It has a composite video jack, but only monochrome comes out of it. I would like to use this machine with my composite color monitor in color. If anyone out there knows anything about where I might be able to get a RGB to composite adaptor, I would much appreciate hearing about it. Thanks in advance, as they say. -- (Randy Horton) allegra| hplabs | topaz |-!pyramid!ranhome!randy decwrl |
tj@utcs.UUCP (06/23/86)
As an opposite request to this, I am interested in information about an RGB to shades of gray adapter. I run a monochrome composite monitor off a color card and sometimes its horrible to read text where some fancy programmer has set color attributes when not necessary! I want shades of gray and don't know how to get it. tj utcs!tj uucp tj at utoronto bitnet 416-978-4924
randy@chinet.UUCP (randy) (06/25/86)
In article <1986Jun23.11:14:40.29844@utcs.uucp> tj@utcs.UUCP (tj) writes: > >As an opposite request to this, I am interested in information about >an RGB to shades of gray adapter. In the July 86 Byte on page 267 is mention of "The Missing Link" from Active Components. It is a rgb to composite converter that produces 16 shades of grey. The cost is $29.95 (!) -- .. that's the biz, sweetheart... Randy Suess chinet - Public Access UN*X (312) 545 7535 (h) (312) 283 0559 (system) ..!ihnp4!chinet!randy
lacasse@randvax.UUCP (Mark LaCasse) (06/27/86)
In article <1986Jun23.11:14:40.29844@utcs.uucp> tj@utcs.UUCP (tj) writes: >As an opposite request to this, I am interested in information about >an RGB to shades of gray adapter. I run a monochrome composite monitor >off a color card and sometimes its horrible to read text where some fancy >programmer has set color attributes when not necessary!... >utcs!tj uucp >tj at utoronto bitnet >416-978-4924 Robert Dukelow (a fellow netter) just told me about a product for this. Neither of us has tried it. Its been on the market since 1981, and is the only product of a small company. The people there I talked to by phone seemed pretty smart. Its called "The Grayscaler". An ad reads: "Create crisp composite video directly from your color graphics card RGB port and enjoy sixteen shades of brightness. Ordinary monitors come alive with complete RGB equivalent software compatibility for the IBM PC, XT, AT, Compaq, Columbia, and other compatibles and color cards. "Miniturization packs a high speed D/A, synch circuit, and line driver in a single cubic inch module. External installation on RGB connector does not use slot. Phone jack output. Interference-causing color is completely sidestepped by Grayscale." On the phone they said you needed a COMPOSITE (analog) monitor, and it would not work with a "TTL" monitor (e.g. IBM Monochrome, Amdek 310A). Company: $59.95 + $2.00 + 6% sales tax in California Avocado Computer 17352 Yorkshire Ave. Yorba Linda, CA 92686 714 528-1025 If anyone buys one, please report results to the net. Mark LaCasse qantel!hplabs!sdcrdcf!randvax!lacasse c/o The Rand Corporation cbosgd!ihnp4!sdcrdcf!randvax!lacasse 1700 Main Street lacasse@Rand-Unix Santa Monica, CA 90406 213/393-0411 ext. 7420
sandersr@ecn-pc.UUCP (Robert C Sanders) (06/27/86)
In article <193@ranhome.UUCP> randy@ranhome.UUCP (Randy Horton) writes: > >I remember once seeing advertised somewhere a converter which would convert >RGB video to composite video. ... However, now I have a compatible with a >color graphics card. It has a composite video jack, but only monochrome comes >out of it. I would like to use this machine with my composite color monitor >in color. > >If anyone out there knows anything about where I might be able to get a RGB to >composite adaptor, I would much appreciate hearing about it. > I know of the exact board that you are looking for: it is the "Truevision Composite Video Adaptor", made by AT&T, Computer Systems Group, Indianapolis Indiana. This adaptor was designed for AT&T's TARGA series video boards, can also act as a stand-alone unit. It has external connectors for: RGB input; NTSC generating RS170A Color Composite video output; NTSC Color Composite (RS170A) input; generating RGB output. It plugs into any IBM PC compatible, and has software included that can set the saturation, various hues, brightness, and contrast. NOTE!!! The RGB output of most computer video boards is IBM-standard TTL RGB (or really psuedo-RGB) at 0 to ~3.8 volts, with separate vertical sych, and hori-sync, and intensity lines. Analog RGB, or broadcast RGB, uses 4 pins -- composite sync, and the three colors at 0 to .714 volts. To use the board with a standard TTL RGB board, you will have to use resistor networks to pad the voltage levels down, and a NOR gate to generate negative-going composite sync from H-sync and V-sync, and with a pad to bring the voltage down. Lastly, in your resistor pads, use a resistive summer to add the different intensity lines; you could even use high-frequency OP amps as adders, running at 6 MHz or so. The board goes for $495 from AT&T computer distributors. - bob -- ------------ Continuing Engineering Education Telecommunications Purdue University "Time is a mouse that requires constant feeding..." -- me ...!ihnp4!pur-ee!pc-ecn!sandersr
dea@hpcesea.HP (Bob Dea) (06/30/86)
In the latest issue of PC Tech Journal (Vol 4 # 7) an article by Michael Covington "A BETTER CGA" describes how to convert your CGA to produce distinct shades of gray by removing a risto r