yahnke@vms.macc.wisc.edu (Ross Yahnke, MACC) (11/20/90)
The product spec sheet for the Apple 8.24 card sez: "Output Signals -
RS-343 standard. Supports RS-170 timing standard for interlaced
video with overscan and underscan modes"
Does this mean the card can produce a NTSC signal? Could I just
plug my VCR into it and record the Mac video display?
>>> yahnke@macc.wisc.edu <<<tom@alias.UUCP (Tom Burns) (11/21/90)
In <4763@dogie.macc.wisc.edu>yahnke@vms.macc.wisc.edu(Ross Yahnke, MACC) writes: >RS-343 standard. Supports RS-170 timing standard for interlaced [...] >Does this mean the card can produce a NTSC signal? Could I just >plug my VCR into it and record the Mac video display? Nope, sorry. RS-343 is a 60Hz non-interlaced analog video signal running anywhere from ~30KHz to ~60KHz (horizontal scan rate). RS-170 is an interlaced 30Hz video signal running at 15.75 KHz. So if you have three 'monochrome' RS-170 signals R, G, and B, they can be encoded into an NTSC signal (RS-170A - the 'A' is the difference). An encoder will cost you anywhere from a few hundred to tens of thousand $$. Typically Mac cards which support RS-170 signals say somewhere that you can take just the green channel and record it on your VCR as a B&W video signal. This works about as well as you'd expect. -- Tom Burns, aka "The Video Guy" at: | "Ebben ne'andro lontana" - La Wally Alias Research Inc. (416) 362-9181 | Fax: (416) 362-0630 110 Richmond St E, Toronto M5C 1P1 | DOMAIN: tom%alias@csri.toronto.edu