Right, so you need a ST PSU to standard molex 4 pin then ? I can probably just make you one if that's easier.ijor wrote: Fri Aug 25, 2023 8:08 pm But only the "normal" 6-pin connector is populated in my board. Otherwise I could connect it directly to one of the 4-pin AUX ports. No big deal. I'll use a couple of jumper cables for 5V and GND.
H5 with external PSU. Power requirement
Re: H5 with external PSU. Power requirement
Re: H5 with external PSU. Power requirement
It’s not good having exposed PSUs especially the original ST one where the heat sink is pretty much live to touchijor wrote: Fri Aug 25, 2023 4:56 pm I need to use an external PSU for my H5 motherboard. Of course it is possible to just use a standard ST PSU with some kind of cable extension. But, honestly, I don't feel very comfortable with that kind of setup. If going with an external PSU, it will probably be much safer to use something fully enclosed.
I have seen in @Badwolf’s videos he has what looks like a 3D printed cover over his PSUs. @Badwolf is there a stl for that cover?
Re: H5 with external PSU. Power requirement
Thanks a lot for the offer, Exxos. But I tried a couple of "Molex PSU" units I have with jumper cables and it doesn't work. Seems they can't deliver enough power.exxos wrote: Fri Aug 25, 2023 8:10 pm Right, so you need a ST PSU to standard molex 4 pin then ? I can probably just make you one if that's easier.
http://github.com/ijor/fx68k 68000 cycle exact FPGA core
FX CAST Cycle Accurate Atari ST core
http://pasti.fxatari.com
FX CAST Cycle Accurate Atari ST core
http://pasti.fxatari.com
Re: H5 with external PSU. Power requirement
Thats a shame. 2amps should be enough. Probably not a true specced device as is common these days.ijor wrote: Sun Aug 27, 2023 10:57 pm Thanks a lot for the offer, Exxos. But I tried a couple of "Molex PSU" units I have with jumper cables and it doesn't work. Seems they can't deliver enough power.
Maybe something like a ITX PSU or simple DC jack PSU would be best ?
https://www.ebay.com/itm/364270000070
Re: H5 with external PSU. Power requirement
So, using a bit of perspex that I had lying about I have created a cover for @ijor's PSU and an extension lead. Yes, I could have created a nice 3D model and printed it but this took about 30 mins to make.
Re: H5 with external PSU. Power requirement
Ah, mine are just very flimsy little things that I've guessed at dimensions for and then just gone at with side cutters to make it work. Not sure an STL would be very useful & the result is only there to stop me brushing something I oughtn't.Icky wrote: Sun Aug 27, 2023 5:08 pm I have seen in @Badwolf’s videos he has what looks like a 3D printed cover over his PSUs. @Badwolf is there a stl for that cover?
Your little case looks 10x better.
Although if I were me, I'd probably stick a low-end industrial PSU in an off-the-shelf project box and run a line of 5V-only DC flex to the case with a barrel jack, adapting what I need inside. Use a cheap boost board for the 12V (again, inside the case) if required.
One of these, probably: https://www.xppower.com/portals/0/pdfs/SF_LCW15.pdf.
They're a tenner at Farnell, for example, and will run a lot cooler than an original, I'm sure.
BW
DFB1 Open source 50MHz 030 and TT-RAM accelerator for the Falcon
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
Re: H5 with external PSU. Power requirement
Wow, this looks fantastic. Amazing job!!!Icky wrote: Mon Aug 28, 2023 3:33 pm So, using a bit of perspex that I had lying about I have created a cover for @ijor's PSU and an extension lead. Yes, I could have created a nice 3D model and printed it but this took about 30 mins to make.
...
http://github.com/ijor/fx68k 68000 cycle exact FPGA core
FX CAST Cycle Accurate Atari ST core
http://pasti.fxatari.com
FX CAST Cycle Accurate Atari ST core
http://pasti.fxatari.com
- rubber_jonnie
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Re: H5 with external PSU. Power requirement
Having just pulled a PSU out of the drawer, it is marked 5v @ 3a and 12v @1.6a.
I have seen up to 5v@2.8a on a machine I was testing using a bench PSU while accessing a real floppy drive.
I have seen up to 5v@2.8a on a machine I was testing using a bench PSU while accessing a real floppy drive.
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...
