A1200 NTSC>PAL motherboard swap

MeetDKing

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I'm planning on picking up an A1200 in the near future however it's a NTSC version as that's the only NOS 1200 I've been able to find. I heard a lot of PAL games can be temperamental running on an NTSC (such as with sound cutting out and such) so I was planning on swapping out the motherboard with a PAL version. I'm not sure on the NTSC motherboard revision number other than it's an Escom variant but the PAL motherboard is 1D4. My question is are the motherboards easily swappable or would some ports be different and not fit in the case?

I'm guessing I'd have to pick up a new power supply as well but that's not really a major concern. Are there any other gotchas I'd need to be aware of to do something like this?
 

rkauer

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All motherboards will fit perfectly in all cases (for the same Amiga model, that's it).
 

desiv

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I had heard that changing an NTSC Amiga to PAL is just lifting or grounding (or something) 1 pin on 1 chip??

There was someone on one of the forums that put in a switch for this...

I'll see if I can find that post..

Not sure if that is all that's required tho...

desiv

---------- Post added at 15:48 ---------- Previous post was at 15:03 ----------

Found it: It's in this thread:
http://www.lemonamiga.com/forum/viewtopic.php?t=4534&postdays=0&postorder=asc&start=15

(you have to scroll down to get to the A1200 part)
..and he says this:

I don't really think this mod is butchering. (I'm the one who did it.)
You just gently lift pin 41 on the alice, and then route it to a switch.
Turn the switch on, you connect to ground and have a NTSC machine.
Leave floating, and the internal pullup selects pal.

I mounted the switch on the knockout behind the floppy, so there is no permanent modification to the outer case.

desiv
 

rkauer

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There is a zero-Ohm SMD resistor (also known as SMD soldered jumper) on the underside of the motherboard which routes pin 41 of Alice (Agnus successor) to ground. I'll check the schematics to see its code.

It's easy to sack the resistor and route two wires from the pads to a switch.

Just remember the video encoding will stand in NTSC mode, and the motherboard crystal will not be the correct type (NTSC is 28.6363MHz, and PAL is 28.3875MHz), so games that relies on the motherboard timings will still not work.

A RGB monitor or scandoubler is mandatory for this hack.
 

MeetDKing

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All motherboards will fit perfectly in all cases (for the same Amiga model, that's it).

Thanks. That's the answer I was hoping for.

My soldering skills are abysmal at best so I probably wont go the modifying route and will just use the NTSC board for a tower project or something. Or just keep it around as a backup.
 

dabone

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For the hack having good soldering skills is a must.
(I'm the one from the lemon posts.)
I ended up selling my ntsc amiga and getting a real uk one from a member here. Currently it's put up and the vic 20 is out in its place.

Pal is so much nicer to have than ntsc for playing games and demos. Just make sure you don't have any fluorescent blubs in the room, 50 and 60hz fighting can make you sick to your stomach.


Later,
dabone
 

Merlin

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Just make sure you don't have any fluorescent blubs in the room

What's a fluorescent blub? Is it some kind of monster.....??

Steve McQueen stars in...... THE BLUB!!

:LOL:
 

MeetDKing

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Just make sure you don't have any fluorescent blubs in the room, 50 and 60hz fighting can make you sick to your stomach.

Maybe a dumb question... But since most (all?) LCD monitors utilize fluorescent backlighting would that be a problem? That's probably what I'll be using with it eventually. I also have CFL in a lamp 6 feet away or so but that can easily be changed if it becomes a problem.
 

rkauer

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Nope, the fluorescent lamp inside the LCD monitors uses a very high frequency, so no strobe effect.
 
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