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guybrush · 10 July 2021, 07:40

How do I check for current on load? Should I start playing a mod and then measure with the multimeter?
And is there a way to figure out which power brick would work with the picoPSU? I assume others are using this mod too; and while not all power bricks are created equal; there should be a reliable way to find one that works for sure with the Pico

I am tempted to just throw out of the window the Pico idea; although there is not much in terms of alternatives at that point, since even an ATX PSU may have the same exact issues of the pico at this point. And I am not that keen on using a 20+ year old PSU.

Considering that the amiga just need 12v and 5V for most of its circuitry, and -12V for the audio circuit, I find strange that nobody in the community made a small PSU; all I found are ATX mods or Pico mods

Looking at the power consumption, unless I have the numbers wrong, the Amiga 1200 with the Blizzard 1230 and a Gotek/floppy should use not more than 10-15W at full load; this means that if the power input to the Pico is 12V in, the current needed is less than 2A; so my 10A brick is supplying way more current than what needed; as such the issue must be in how clean the signal is. I just ordered a different PicoPSU from a different company; will give a try and see if that one does the same as the Pico I have; just so I can rule out the Pico issue itself.

I have 3 different power bricks, at 3, 5 and 10A; so the chances that all 3 are bad are quite on the low side; or they all lack something that the Pico is expecting (-12V rail); which means I have no clue how to fix this. The AC bricks on Mouser do not seem to have clear data about the -12V rail; unless I am missing something:

https://www.mouser.com/Search/Refine...128+4292906361

10 July 2021, 07:40	#8
guybrush Registered User Join Date: Jul 2015 Location: usa Posts: 243	How do I check for current on load? Should I start playing a mod and then measure with the multimeter? And is there a way to figure out which power brick would work with the picoPSU? I assume others are using this mod too; and while not all power bricks are created equal; there should be a reliable way to find one that works for sure with the Pico I am tempted to just throw out of the window the Pico idea; although there is not much in terms of alternatives at that point, since even an ATX PSU may have the same exact issues of the pico at this point. And I am not that keen on using a 20+ year old PSU. Considering that the amiga just need 12v and 5V for most of its circuitry, and -12V for the audio circuit, I find strange that nobody in the community made a small PSU; all I found are ATX mods or Pico mods Looking at the power consumption, unless I have the numbers wrong, the Amiga 1200 with the Blizzard 1230 and a Gotek/floppy should use not more than 10-15W at full load; this means that if the power input to the Pico is 12V in, the current needed is less than 2A; so my 10A brick is supplying way more current than what needed; as such the issue must be in how clean the signal is. I just ordered a different PicoPSU from a different company; will give a try and see if that one does the same as the Pico I have; just so I can rule out the Pico issue itself. I have 3 different power bricks, at 3, 5 and 10A; so the chances that all 3 are bad are quite on the low side; or they all lack something that the Pico is expecting (-12V rail); which means I have no clue how to fix this. The AC bricks on Mouser do not seem to have clear data about the -12V rail; unless I am missing something: https://www.mouser.com/Search/Refine...128+4292906361 Last edited by guybrush; 10 July 2021 at 08:04.