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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Whitesnake on May 25, 2004, 01:25:12 PM

Title: A600 PAL to NTSC how is it done?
Post by: Whitesnake on May 25, 2004, 01:25:12 PM

I'm interested to know if there is an easy method on changing a PAL A600 to NTSC. :-)

Title: Re: A600 PAL to NTSC how is it done?
Post by: jj on May 25, 2004, 02:32:59 PM

hold down both mouse buttons on boot up to get to the early start up menu and then press either space or tab, cant remeber which to change to NTSC and change it to NTSC in the display menu

Title: Re: A600 PAL to NTSC how is it done?
Post by: leirbag28 on May 25, 2004, 02:48:38 PM

@JJ

 I think he meant physically.

But by holding the 2 mouse buttons as soon as you turn on the A600 a menu pops up. Just hit any key on the keyboard and it becomes PAL, hit any key again and it becomes back to NTSC (this is just so that you can view the menu if your tv doesnt support one)........but to actually boot in one of these modes you have to select it in the menu, then boot.

now as for physically, you really cannot convert it. its not like the A2000 or 3000 or 4000, which you could supposedly change them by selecting a jumper.

In your case I think you may have to unsolder and resolder some chips.

Title: Re: A600 PAL to NTSC how is it done?
Post by: Whitesnake on May 25, 2004, 03:00:22 PM

The bios menu on the A600 2.05 Kick does not have an NTSC/PAL option like the 3.1 Kick.

Title: Re: A600 PAL to NTSC how is it done?
Post by: Kronos on May 25, 2004, 03:30:27 PM

Sure you can ! Same way as I did it on my old A2000 (which was so old, that it didn't have the jumper):

Connect one pin of Agnus to GND (if I could just remeber which one ).

Title: Re: A600 PAL to NTSC how is it done?
Post by: SamuraiCrow on May 25, 2004, 03:55:20 PM

I thought you would have to change the crystal on the mobo also because the clock speed of an NTSC Amiga is slightly faster...  :-(

Title: Re: A600 PAL to NTSC how is it done?
Post by: Kronos on May 25, 2004, 04:09:25 PM

Well you can allways hook an external crysatl onto the RGB-port if you really miss those 50kHz in CPU-speed  :-P

Title: Re: A600 PAL to NTSC how is it done?
Post by: adolescent on May 25, 2004, 04:28:52 PM

The A600's 8375 2M Agnus doesn't have the PAL/NTSC pin anymore.  So, AFAIK, it's not possible to build a simple hardware switch like the A500/A2000.

Title: Re: A600 PAL to NTSC how is it done?
Post by: Ilwrath on May 25, 2004, 05:39:30 PM

Good ole' degrader with the "survive resets" option might be about the best idea.  Then you could make it an NTSC A600 until power off.  ;-)

Title: Re: A600 PAL to NTSC how is it done?
Post by: Stedy on May 25, 2004, 11:45:01 PM

Hello,

The A600 schematics (http://www.ianstedman.co.uk/Downloads/a600-schematics.zip) on page 4 (video) have an extra circuit for PAL users so that the Composite/RF output is the correct frequency. Not too sure what would happen if you disabled it.

X1, the system clock should be changed from 28.37512 MHz to 28.63636 MHz.

U12, the CXA1145 video encoder has an NTSC/PAL pin. I think removing R203 and fitting in the space of R202, will force NTSC. On the A1200 which has NTSC/PAL selectable, this pin is controlled by the A1200s _NTSC signal.

In answer to your original question, there is no easy way!  :-D