What is the A1200 PSU (physically) lightweight with 3A on the 5V line? And the A500 a physically heavy one with 5A on 5V line?
There is also a physically lightweight PSU with 5A on 5V line. I think this is more of a switch mode design.
I've found in the PSUs there is a resistor that has heat marks, so I replace those with higher wattage versions.
The latest member of the family
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Higgy
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rubber_jonnie
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Re: The latest member of the family
I'm sure it'll be fine, seems like a really solid machine.JezC wrote: 29 Jan 2025 21:23 I'm just hoping you have a lot less hassle with the A500...
:crossed1:
If I can get the 1200 stable, which it seems to be after cleaning the connectors and re-capping the accelerator (all the caps were reading really low when I tested them) then were good to go.
The other thing I noticed about the accelerator was all the jumpers were a bit loose, so they're all replaced too. Just need to replace the battery for the RTC, luckily a CR2032, and it should be fine.
The A500 RAM expansion should be here today too.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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stephen_usher
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Re: The latest member of the family
The alternative to a trap door RAM expansion is to populate the extra RAM sockets on the motherboard, if you have a Rev.6 board.
Intro retro computers since before they were retro...
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
ZX81->Spectrum->Memotech MTX->Sinclair QL->520STM->BBC Micro->TT030->PCs & Sun Workstations.
Added code to the MiNT kernel (still there the last time I checked) + put together MiNTOS.
Collection now with added Macs, Amigas, Suns and Acorns.
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rubber_jonnie
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Re: The latest member of the family
Much appreciated, thanks. All I need now is a load of floppies that work!HigashiJun wrote: 30 Jan 2025 01:26No worries, but please give me some time.rubber_jonnie wrote: 29 Jan 2025 13:11 As for the GW I'm just finding it won't write ADF files at all. @HigashiJun if you have any pointers I'd be grateful.
I have to take out my GW from the closet, find my 3.5" floppies and take a screenshot of the settings.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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rubber_jonnie
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Re: The latest member of the family
Thanks for the info, I'll see how the original one goes once the re-cap is done. I could also get a Meanwell replacement for the guts, but I think it'll be ok now the accelerator seems to have settled down.HigashiJun wrote: 30 Jan 2025 01:29 Oh, and BTW, I have the following PSU for my AMIGA 1200:
https://amigastore.eu/en/683-a-power-hq ... 01200.html
It works really great even with a TF1260 fitted.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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rubber_jonnie
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Re: The latest member of the family
I haven't opened it up yet :)stephen_usher wrote: 30 Jan 2025 08:54 The alternative to a trap door RAM expansion is to populate the extra RAM sockets on the motherboard, if you have a Rev.6 board.
The trapdoor expansion was only £10 so that'll do for now until I open it up and think about what I may do. I suspect I'll at least do an RGB2HDMI, though I'm not overly bothered about acceleration TBH.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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JezC
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Re: The latest member of the family
I'd be interested to know which one you went for...just in case I can't repair the one I have that has suffered the attack of the Varta battery...heavily inspired by the video from BW...
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rubber_jonnie
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Re: The latest member of the family
It should be here this afternoon, I picked one that had CR2032 as they don't tend to leak and it's apparently working. I'll post pics when it arrives.JezC wrote: 30 Jan 2025 11:35I'd be interested to know which one you went for...just in case I can't repair the one I have that has suffered the attack of the Varta battery...heavily inspired by the video from BW...
Speaking of CR2032's I just replaced the one on my accelerator, so I should be back in the land of real time on the 1200 imminently.
Varta's and Maxell batteries have anded far too many computers for my liking.
On another subject, I used to have a Amiga tank mouse for my 1200 and now I can't find it, quite annoying as it would be nice to have one for each machine.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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Higgy
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- Location: Somerset
Re: The latest member of the family
With the Gotek you can have an 'onscreen' display, you need an additional STM32 blue pill. Saves cutting case or having to look sideways at the Gotek if you have an OLED screen.
https://github.com/keirf/flashfloppy-osd/wiki
I think a rotary controller is a real benefit to easily change disk images. I mounted mine at the back, although numpty here fitted so it blocks a case screw with the rotary knob on.
But how many times do you need to open the case, we never do right :lol:
A500s (not 500 plus) seems pretty bullet proof. I've had it where one did not boot, but an IC just needed pulling and pushing back in.
A1200 PCB needs caps changing. Also one thing that caught me out on newer accelerator cards, is that some (seems to be 1B revisions) don't have a chamfer on the trapdoor edge connector. This can wreck the connector on the accelerator. Easily sorted with a file.
https://github.com/keirf/flashfloppy-osd/wiki
I think a rotary controller is a real benefit to easily change disk images. I mounted mine at the back, although numpty here fitted so it blocks a case screw with the rotary knob on.
But how many times do you need to open the case, we never do right :lol:
A500s (not 500 plus) seems pretty bullet proof. I've had it where one did not boot, but an IC just needed pulling and pushing back in.
A1200 PCB needs caps changing. Also one thing that caught me out on newer accelerator cards, is that some (seems to be 1B revisions) don't have a chamfer on the trapdoor edge connector. This can wreck the connector on the accelerator. Easily sorted with a file.
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rubber_jonnie
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Re: The latest member of the family
I've seen people do this before on ST's but I didn't think it was necessary to have an ST32 Blue Pill, but I do have a couple spare so might be worth a look, thanks. I remember when I first owned an A500 BITD, it was a very solid reliable machine.Higgy wrote: 30 Jan 2025 12:13 With the Gotek you can have an 'onscreen' display, you need an additional STM32 blue pill. Saves cutting case or having to look sideways at the Gotek if you have an OLED screen.
https://github.com/keirf/flashfloppy-osd/wiki
I think a rotary controller is a real benefit to easily change disk images. I mounted mine at the back, although numpty here fitted so it blocks a case screw with the rotary knob on.
But how many times do you need to open the case, we never do right :lol:
A500s (not 500 plus) seems pretty bullet proof. I've had it where one did not boot, but an IC just needed pulling and pushing back in.
A1200 PCB needs caps changing. Also one thing that caught me out on newer accelerator cards, is that some (seems to be 1B revisions) don't have a chamfer on the trapdoor edge connector. This can wreck the connector on the accelerator. Easily sorted with a file.
I checked my label and the A1200 caps were done in 2020, doesn't time fly when you're having fun!
Can't say I'd really noticed a chamfer or not, but I'm loath to remove the accelerator again as once it's in and working it seems stable. I just replaced the CR2032 RTC battery so it shouldn't need to come out again, but I'll check if I have to remove it any time soon, thanks again.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
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