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StompinSteve · 04 February 2023, 08:12

My Amiga 3000 has arrived from the USA and I went about changing Jumper J200 to PAL and I swapped the oscillator with a 28.37516 MHz PAL version.

I finished the 110V -> 230V conversion of the PSU. I followed this manual and the mod went fine: http://amiga.serveftp.net/A3000_HardwareGuide/psu.html
I cut the wire and used heat-shrink to make sure those (now) two wires can never touch.

The system now runs directly of 230V and is perfectly stable.
I measured the voltages on the 15pin motherboard connector before and after and the voltages stayed the same. So that's good. I hooked up the PSU to the A3000 and it booted fine but...
... it still seems to run in NTSC mode. PAL Video look like crap, NTSC Video is fine. Lotus II music still too fast.

Unfortunately, one leg of the old oscillator broke off and was stuck in it's tiny little socket. I would not come out, not even with mild controlled violence and verbal encouragement.
A stump stayed behind in the socket. So what I did is cut the same pin on the new (PAL) osc. to length, then gently pressed the other 3 legs of the osc. in their sockets until the shortened pin touched the stump of the old pin. I then carefully soldered the stump (by lack of a better word) and the shortened pin of the new oscillator together.

What if the solderjoint is not good. Cold joint, not connected properly. It looks good but what if it isn't? Could that cause this effect? The pin that broke off is the one directly next to the pin marked with a dot in the corner (see the 3rd foto).

With my trusty multimeter, I tested continuity between each of the 4 legs of the new PAL oscillator with their solder-points at the underside of the motherboard. I get solid, stable readings for all four.

SysSpeed 2.6 shows "Power" to be 60Hz. In both PAL and NTSC Highres Laced workbench 3.1 screenmodes. See attached screenshots. We don't have a 60Hz grid here (it's 50) and the PSU is now plugged in directly into a 50hz 230V wall outlet so i'm a bit confused.

Broken pin of old oscillator
https://eab.abime.net/attachment.php...1&d=1675494851

SysSpeed power-info after PSU mod.
https://eab.abime.net/attachment.php...1&d=1675494851
https://eab.abime.net/attachment.php...1&d=1675494851

04 February 2023, 08:12	#1
StompinSteve Village idiot Join Date: Jun 2021 Location: Switzerland Posts: 267	Amiga 3000 conversion to PAL not working My Amiga 3000 has arrived from the USA and I went about changing Jumper J200 to PAL and I swapped the oscillator with a 28.37516 MHz PAL version. I finished the 110V -> 230V conversion of the PSU. I followed this manual and the mod went fine: http://amiga.serveftp.net/A3000_HardwareGuide/psu.html I cut the wire and used heat-shrink to make sure those (now) two wires can never touch. The system now runs directly of 230V and is perfectly stable. I measured the voltages on the 15pin motherboard connector before and after and the voltages stayed the same. So that's good. I hooked up the PSU to the A3000 and it booted fine but... ... it still seems to run in NTSC mode. PAL Video look like crap, NTSC Video is fine. Lotus II music still too fast. Unfortunately, one leg of the old oscillator broke off and was stuck in it's tiny little socket. I would not come out, not even with mild controlled violence and verbal encouragement. A stump stayed behind in the socket. So what I did is cut the same pin on the new (PAL) osc. to length, then gently pressed the other 3 legs of the osc. in their sockets until the shortened pin touched the stump of the old pin. I then carefully soldered the stump (by lack of a better word) and the shortened pin of the new oscillator together. What if the solderjoint is not good. Cold joint, not connected properly. It looks good but what if it isn't? Could that cause this effect? The pin that broke off is the one directly next to the pin marked with a dot in the corner (see the 3rd foto). With my trusty multimeter, I tested continuity between each of the 4 legs of the new PAL oscillator with their solder-points at the underside of the motherboard. I get solid, stable readings for all four. SysSpeed 2.6 shows "Power" to be 60Hz. In both PAL and NTSC Highres Laced workbench 3.1 screenmodes. See attached screenshots. We don't have a 60Hz grid here (it's 50) and the PSU is now plugged in directly into a 50hz 230V wall outlet so i'm a bit confused. Broken pin of old oscillator https://eab.abime.net/attachment.php...1&d=1675494851 SysSpeed power-info after PSU mod. https://eab.abime.net/attachment.php...1&d=1675494851 https://eab.abime.net/attachment.php...1&d=1675494851 Attached Thumbnails Last edited by StompinSteve; 04 February 2023 at 09:53.