need confirmation for a1200 pal/ntsc
 

hi all,

I was reading the following for Pal/NTSC conversion and vica versa. I did do this to an A500 and never used the resistor. Is the resistor needed when applying this to the A1200 ?...


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Q. Is there an internal jumper on the A1200 to set it to default to PAL or NTSC video?
A. No, but if you're really motivated, you can rig this up. My thanks to Tetsuo Oda and Byron Montgomerie, who provided the information that connecting pin 41 of the Alice custom chip to ground causes the A1200 to default to NTSC, while pulling this pin high (disconnecting it from the motherboard and connecting it to +5V through a 4.7k resistor) will make the default power-up state PAL. I would point out that making a modification like this on a surface-mount chip is difficult at best, and you may end up needing an expensive motherboard replacement, or, at worst, a dead A1200 that needs an expensive replacement motherboard available. In most cases, using the boot menu (obtained by pressing both mouse buttons on power-up or reset) to switch to PAL is sufficient. However, with some games, the hardware patch will be necessary to insure proper timing (changing to PAL via the boot menu might make a 50 Hz game run at 60 Hz timing, or vice versa).
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I'd like to give this a shot on my NTSC machine and just wondering if this mod is good.

thanks
kipper

I'm guessing they would not have made 2 different mobo's just for PAL/NTSC especially if Alice has the ability to do it. I'd guess that there is provision somewhere on the board that a link and 4.7k are soldered to.
Find where these are and it would make installing a switch a lot easier and and better than lifting Alice's legs. oooer.
EDIT: If anyone has the schematics I'll take a look (or maybe someone already knows).

It would be nice not to have to lift the legs. It can be done with a bent safety pin and soldering iron, but that would be the last resort. If pin 41 is tied to ground then i dont know you could hold it high without either lifting the pin or cutting a trace somewhere.

Why are you keen on doing this, would be my question?

Hi Akira,

I have a Pal A1200 and an NTSC one. The Pal one has indivision setup on it and the indivision card keeps backing off slightly causing graphic errors non loading etc. I've tried a few ways to hold it down and to no joy. if i pick up the A1200 and put it down a little too hard or even just slightly twist the case when i move it the card becomes unseated so what i want to do is to try to make my NTSC A1200 into PAL so i dont have to jump into early startup all the time to change modes. I tried my indivision on the NTSC A1200 and the card sits fine on that hence the reason for wanting to swap that one from NTSC to Pal. (Not to mention that most software out for the Amiga is pretty well all European Pal). I don't want to have to keep reseating the card all the time as we all know what will happen eventually, so i think its time to stop the reseating thing (and mabbe be able to put the screws back in the A1200 at last)

Best to dremel / sand down the socket of the Indivision as per the guides

I received it already presanded, its right down to the top of the pins in the socket so its pretty well a no-go on the sanding :( (it is one of the HP chips in there too. Iwas even thinking about applying bits of solder to the top of the chip to make it fatter but thats too risky

I have the solution to all them push on connectors. Just open up the 1200 and place this on top of the flicker fixer. These connectors should be banned! they cause no end of trouble.
http://brick.0x46.net/Brick.jpg

Speaking as a pretty continually frustrated owner of an apollo 620, I have to concur with Dimlow :D

Hey Dimlow...
How much for the brick, do you have the ipf or is it ADF only :)

I am gonna pull the pin on it today and see what the result is... i also read somewhere that pin 5 is held high interally so mabbe a 5v supply thru a 4.7K resistor may not be needed

k,

So here is my NTSC motherboard. I lifted pin 41 on Alice.... Voila!! I have PAL mode, no 4.7K resistor applied and all seems well, now to put a switch that will ground the wire on it so i can toggle Pal/NTSC whenever i want :)


Edit... now when i jump into early startup it defaults to PAL mode when pin 41 is open




heres a piccie

http://www.kipper2k.com/amiga/palmod.jpg

Do you see that green "resistor" near the lifted pin? It routes pin 41 to ground.

Was (and still is) only a matter of sack it out and route the (now open) pads to a switch...:rolleyes

Revising the schematics: it is R203. Just remove it for to force PAL, short the pads to NTSC.

Congratulations on your mod and big balls! :D

lol, now ya tell me :)

I did say lol.
Rkauar is reffering to a 0 ohm link.

That's why I call it "resistor", not resistor (without quotes). Also a ZERO Ohm resistor (or very near zero, in truth) still is a resistor. ;)

Because nothing is a perfect conductor :)

So would lifting Alice's pin 41 on an NTSC CD32 make it PAL just like A1200?

I never really got an answer in other threads about that...

PZ.

Aye Fingers, It's the exact same chip ;)
I would follow rkauers suggestion though if the CD32 has the same Zero Ohm resistor.

TC :cool

Hi,

just to verify that the NTSC version i modded does not connect to any of the nearby zero ohm resistors, i metered the pad of pin 41 to those 3 zero ohm resisters close to the pad and they were not giving a reading on ohms so i dont believe they are directly connected to the pad.