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Article #5742

Re: NTSC on a PAL Amiga

#5742
From: Kurt Koller
Date: Wed, 10 Oct 1990 20:05
71 lines
3442 bytes
Here is a PAL/NTSC switch setup I developed for those machines with a BIG FAT
AGNUS...
 
          How to install the NSTC / PAL switch into your Amiga 2000
         ===========================================================
 
 
 
         This modificiation will work on a default NTSC or PAL A2000.
 
      First off take the cover off your machine and remove the drive and
      Power supply chassis ( disconnect the power supply and the disk
      drive ribbon cable from the motherboard...make sure you remember
      which end of the cable goes to which pins!!! ). Then remove the
      whole unit from the machine and set it aside...
 
  
  
        A. Now look for the FAT AGNUS chip on the motherboard, it should
           say FAT LADY near the chip....now check the number on top of 
           the chip, You MUST have the new 1 Meg Agnus (Super Agnus part
           #8372).
   
        B. Move motherboard jumper J300 from the factory default position
           of pins 1-2 to pins 2-3. This jumper is located under the power
           supply.
  
        C. Locate jumper PADS (no pins) labeled J102 and cut a trace
           between the 2 pads.  BE CAREFUL!! The pads are located right
           next to the AGNUS on the left hand side ( if you are PAL 
           default no need to cut the trace..since PAL is already cut)
  
        D. Mount a SPST switch in a convient place on the outside of the
           Amiga, perhaps next to the power on LED.
  
        E. Run 2 wires from the switch to the 2 pads of J102 (1 wire to
           each pad).
  
      That's it.  With the switch closed (on position), you'll boot in
      NTSC.  With the switch in the open position (off), you'll boot in
      PAL.
  
      NOTE: Most monitors will only require a minor adjustment in vertical
      sync and/or size to work in this manner.  Composite monitors will 
      NOT work.
  
      You must re-boot for the change to take effect, since the jumper
      is only checked at power-up.  If you have problems with Genlocks
      that go in the video slot, run a SPDT switch to the J300 jumper
      to allow you to switch timing between Power supply and Video
      section sources.
 
 
                     Call my BBS - Alt-3 - (612) 228-0127
                                   Koleman
 
 
My BBS is down.  Sorry, I don't feel like editing.
 
You do not need to change the J300 jumper, it's just that if you don't, SI
will report 50hz video, PAL, but 60hz power supply.  IF you have J300 changed,
it reports 50hz on both (true PAL), however you don't REALLY run at 50hz, you
just pretend...
 
There is also a bug in the OS which causes the opening screen to be NTSC
dimesnions on a PAL display, but this doesn't happen all that much.  If you
leave your opening window open (it still is 640x200, not to be confused with
opening screen, 640x256) there is a program I wrote that will change it for
you.  I would FTP it or whatever, but I don't know how!

Kurt "Koleman" Koller - amdahl!bungia!orbit!pnet51!koleman
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From: koleman@pnet51.orb.mn.org (Kurt Koller)
Newsgroups: comp.sys.amiga.tech
Subject: Re: NTSC on a PAL Amiga
Message-ID: <3304@orbit.cts.com>
Date: 10 Oct 90 20:05:02 GMT
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Organization: People-Net [pnet51], Minneapolis, MN.
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