Portable power adapter compatibility?

[Ron's Computer Videos]

I seem to remember back in the day that the Macintosh Portable’s power supply could be used only the Portable… but the PowerBook 100’s power supply (slightly higher amperage) could be used with the Portable.

Is this true? Do you risk damaging anything?

 

[Daniel Hansen]

The consensus of folks much smarter than I is that the Portable depends on the PSU for limiting current draw to 1.5A and that, since the logic board is not isolated or buffered by the battery, using a 2.0A adapter is potentially inviting risk to certain critical IC's (PMGR, SWIM, etc) over the medium-to-long term. Given that suitably specced replacements can be easily found for not much (like this one: https://www.digikey.ca/en/products/detail/triad-magnetics/WSU075-1500/3105438), I think it just makes sense to avoid using the PB adapters, even the 2.0A or 'low power' ones.

 

[nottomhanks]

I can attest that this one works with my 5126: https://www.amazon.com/ZOZO-Regulated-Switching-Replacement-Electronics/dp/B015PXUHYA

 

[Daniel Hansen]

I can attest that this one works with my 5126: https://www.amazon.com/ZOZO-Regulated-Switching-Replacement-Electronics/dp/B015PXUHYA

You know, I was recently wondering about the 5126 because it says '7.5V/2.0A' right on the case... then noticed it says 7.5V/2.0A on the 5120 case. YET the official Portable adapter is only 7.5V/1.5A... and the Apple documentation (and those in the know ever since) stress the use of a 1.5A regulated supply. Bit of a head scratcher for me.